Shellfish in cooking. Structure of molluscum contagiosum. For local drug treatment of molluscs, you can use
Mollusks are one of the most ancient invertebrates. They differ in the presence of a secondary body cavity and rather complex internal organs. Many of them have a calcareous shell, which protects their body quite well from the encroachments of numerous enemies.
This is not often remembered, but many species of this type lead a predatory lifestyle. In this they are helped by the developed salivary gland. By the way, what is the salivary gland in molluscs? This generalizing concept means a fairly wide range of specific organs located in the pharynx and oral cavity. They are intended for the secretion of various substances, the characteristics of which can be very different from our understanding of the word "saliva".
As a rule, molluscs have one or two pairs of such glands, which in some species reach very impressive sizes. In most predatory species, the secret that they secrete contains from 2.18 to 4.25% chemically pure sulfuric acid. It helps both to fend off predators and to hunt their relatives (sulfuric acid perfectly dissolves their calcareous shells). That's what the salivary gland in molluscs is.
Other natural value
Many of the species of slugs, as well as the grape snail, cause great harm. agriculture all over the world. At the same time, it is mollusks that play the most important role in the global purification of water, since they use organic matter filtered from it to feed them. In many countries, large ones are bred on marine farms, as they are a valuable food product that contains a lot of protein. These representatives and oysters) are even used in dietary nutrition.
In the former USSR, 19 representatives of this ancient type were considered rare and disappearing at once. Despite the diversity of mollusks, they should be treated with care, as they are extremely important for the proper functioning of many natural biotopes.
In general, mollusks are often of great practical importance for humans. For example, the pearl oyster is massively bred in many coastal countries, as this species is a supplier of natural pearls. Some shellfish are of great value for medicine, chemical and processing industries.
Want to know interesting facts about shellfish? In the Antique period and the Middle Ages, inconspicuous cephalopods were sometimes the basis of the well-being of entire states, since the most valuable purple was extracted from them, which was used to color the royal robes and robes of the nobility!
Type of shellfish
In total, it has more than 130,000 species (yes, the variety of mollusks is incredible). Mollusks in total number are second only to arthropods, they are the second most common living organisms on the planet. Most of them live in water, and only a relatively small number of species have chosen land as their place of residence.
general characteristics
Almost all animals that are part of this type are distinguished by several specific features at once. Here is the current one general characteristics shellfish:
- First, three layers. Their organ system is formed from the ectoderm, endoderm, and mesoderm.
- Symmetry of the bilateral type, caused by a significant displacement of most of their organs.
- The body is unsegmented, in most cases protected by a relatively strong calcareous shell.
- There is a skin fold (mantle) that envelops their entire body.
- A well-defined muscular outgrowth (leg) serves for movement.
- The coelomic cavity is very poorly expressed.
- There are practically all the same organ systems (in a simplified version, of course), as in higher animals.
Thus, the general characteristics of mollusks indicate that we have before us quite developed, but still primitive animals. It is not surprising that many scientists consider mollusks to be the main ancestors of a large number of living organisms on our planet. For clarity, we present a table in which the characteristics of the two most common classes are described in more detail.
Feature under consideration | Mollusk classes |
|
Bivalves | gastropods |
|
Symmetry type | Bilateral. | Symmetry is absent, some organs are completely reduced. |
The presence or absence of a head | It is completely atrophied, like all organ systems that historically belonged to it. | There is, like the whole set of organs (oral cavity, eyes). |
Respiratory system | Gills or lung (pond snail, for example). |
|
sink type | Bivalve. | One-piece, can be twisted in different directions (pond snails, ampoule) or in a spiral (lake coil). |
Sexual dimorphism, reproductive system | Dioecious, males are often smaller. | Hermaphrodites, sometimes dioecious. Dimorphism is weakly expressed. |
Power type | Passive (water filtration). In general, these mollusks in nature contribute to excellent water purification, as they filter out tons of organic impurities from it. | Active, there are predatory species (Cones (lat. Conidae)). |
Habitat | Seas and fresh waters. | All types of reservoirs. There are also terrestrial mollusks (Grape snail). |
Detailed characteristic
The body is still symmetrical, although this is not observed in bivalve species. The division of the body into segments has been preserved only in very primitive species. The secondary cavity of the body is represented by a bag surrounding the heart muscle and genitals. The entire space between the organs is completely filled with parenchyma.
The body of the majority can be divided into the following sections:
- Head.
- Torso.
- Muscular leg through which movement is carried out.
In all bivalve species, the head is completely reduced. The leg is a massive muscular process that develops from the base of the abdominal wall. At the very base of the body, the skin forms a large fold, the mantle. Between it and the body there is a rather large cavity in which the following organs are located: gills, as well as the conclusions of the reproductive and excretory systems. It is the mantle that secretes those substances that, having reacted with water, form a strong shell.
The shell can be either completely solid or consist of two flaps or several plates. This shell contains a lot of carbon dioxide (of course, in a bound state - CaCO 3), as well as conchiolin, a special organic substance that is synthesized by the body of the mollusk. However, in many species of mollusks, the shell is completely or partially reduced. In slugs, only a microscopic plate remains from it.
Characteristics of the digestive system
gastropods
There is a mouth at the front end of the head. The main organ in it is a powerful muscular tongue, which is covered with a particularly strong chitinous grater (radula). With its help, snails scrape off a coating of algae or other organic matter from all accessible surfaces. In predatory species (we will talk about them below), the tongue has degenerated into a flexible and rigid proboscis, which is intended for opening the shells of other mollusks.
In Cones (which will also be discussed separately), individual segments of the radula protrude beyond the oral cavity and form a kind of harpoon. With their help, these representatives of mollusks literally throw their poison at the victim. In some predatory gastropods, the tongue has turned into a special “drill”, with which they literally drill holes in the shell of their prey to inject poison.
Bivalves
In their case, everything is much simpler. They simply lie motionless at the bottom (or hang, tightly attached to the substrate), filtering through their body hundreds of liters of water with organic matter dissolved in it. The filtered particles go directly to the bulky stomach.
Respiratory system
Most species breathe with gills. There are "front" and "rear" views. In the former, the gills are located in front of the body and their tip is directed forward. Accordingly, in the second case, the tip looks back. Some have lost gills in the direct sense of the word. These large clams breathe directly through their skin.
To do this, they have developed a special skin organ of an adaptive type. In terrestrial species and secondary aquatic mollusks (their ancestors returned to the water again), part of the mantle wraps up, forming a kind of lung, the walls of which are densely penetrated by blood vessels. To breathe, such snails rise to the surface of the water and gain air supply with the help of a special spiracle. The heart, located not far from the simplest "design", consists of one atrium and ventricle.
The main classes that make up the type
How is the type of mollusk divided? The classes of mollusks (there are eight in total) are “crowned” by the three most numerous:
- Gastropods (Gastropoda). This includes thousands of species of snails of all sizes, the main distinguishing feature of which is low speed locomotion and a well-developed muscular leg.
- Bivalves (Bivalvia). Sink with two doors. As a rule, all species included in the class are sedentary, inactive. They can move both with the help of a muscular leg, and by means of jet thrust, throwing out water under pressure.
- Cephalopods (Cephalopoda). Mobile molluscs, shells are either completely devoid of, or it is in its infancy.
Who else is included in the type of mollusk? The classes of molluscs are quite diverse: in addition to all of the above, there are also Spadefoot, Armored and Pit-tailed, Furrowed-bellied and Monoplacophores. All of them refer to the living and healthy.
What fossils does the type of mollusk contain? Classes of molluscs that are already extinct:
- Rostroconchia.
- Tentaculitis.
By the way, the same Monoplacophores were considered completely extinct until 1952, but at that time the Galatea ship with a research expedition on board caught several new organisms that were attributed to the new species Neopilina galatheae. As you can see, the name of the molluscs of this species was given by the name of the research vessel that discovered them. However, in scientific practice this is not uncommon: species are much more often designated in honor of the researcher who discovered them.
So it is possible that all subsequent years and new research missions will be able to enrich the type of mollusk: the classes of mollusks that are now considered extinct may well be preserved somewhere in the bottomless depths of the oceans.
No matter how strange it may sound, but one of the most dangerous and incredible predators on our planet are ... outwardly harmless gastropods. For example, snails Cones (lat. Conidae), whose poison is so unusual that it is used by modern pharmacists in the manufacture of certain types of rare medicines. By the way, the name of the mollusks of this family is fully justified. Their shape is indeed most similar to a truncated cone.
They can be persistent hunters, dealing with floodplain prey with exceptional ruthlessness. Of course, colonial, sedentary species of animals often act as the latter, since other snails simply cannot keep up. The prey itself can be dozens of times larger than the hunter in size. Want to know more interesting facts about shellfish? Yes please!
About methods of hunting snails
Most often, the insidious mollusk uses its most powerful organ, a strong muscular leg. It can attach itself to prey with the equivalent force of 20kg! This is quite enough for a predatory snail. For example, a "caught" oyster opens up in less than an hour with an effort of only ten kilograms! In a word, the life of mollusks is much more dangerous than it is commonly thought ...
Other species of gastropods prefer not to press anything at all, carefully drilling the prey shell with a special proboscis. But this process cannot be called simple and fast with all desire. So, with a shell thickness of only 0.1 mm, drilling can take up to 13 hours! Yes, this way of "hunting" is only suitable for snails...
Dissolution!
To dissolve someone else's shell and its owner himself, the mollusk uses sulfuric acid (you already know what the salivary gland is in mollusks). So the destruction is much easier and faster. After the hole is made, the predator slowly begins to eat its prey out of the "package", using its proboscis for this. To some extent, this body can be safely considered an analogue of our hand, since it is directly involved in the capture and retention of prey. In addition, this manipulator can often be extended so that it exceeds the length of the hunter's body.
This is how snails can get their prey even from deep crevices and large shells. We remind you once again that it is from the proboscis in the body of the victim that a strong poison is injected, the basis of which is chemically pure sulfuric acid (secreted from the "harmless" salivary glands). In a word, from now on you know exactly what the salivary gland is in molluscs and why they need it.
Experienced for many years - carp fishermen, catfish fishermen, yazyatniks, bream fishermen catch big fish on shellfish and is especially good in the second half of summer and early autumn, using them both as bait and bait.
According to scientists, almost all fish would eat mollusks with pleasure, if not for the hard protective shell. But it’s easy for fishermen to remove the shell ...
Shellfish nutrition
Mollusks have a varied diet: they can suck on the bacterial film from various underwater surfaces, they can gnaw, they can grind detritus, they can simply filter organic suspensions ... But they also participate in the food chain and fish eat them with pleasure. The meat of these mollusks is very nutritious, it is rich in vitamins and proteins and can be eaten by almost any fish. Mollusks, like other creatures, live where there is more food, where it is calmer.
Where do molluscs live
shellfish are very widely distributed in our reservoirs: they live in large and small lakes, rivers, in ponds and streams, in stagnant and running water. Probably there is no such place where they would not live. Most of all mollusks are near the coast with thickets of grass, where there are snags, all kinds of shelters. A large number of coils, bits, pearls can collect in places where they are dumped wastewater, where organic matter coming out of the sewer settles to the bottom, which turns this bottom into a real table with “delicacy” products.
It turns out that mollusks from all the surroundings crawl to this place in order to feast in plenty. There is also a fish that eats these mollusks. According to scientists, the biomass of mollusks is much greater than the biomass of other benthic organisms taken together. And this is especially true for our rivers. Under these conditions, mollusks develop very well, sometimes covering the bottom of the reservoir with a continuous carpet.
Types of shellfish
According to scientists, in our reservoirs, there are from 40 to 60 species of "shells". Very small, and these are peas and balls have a shell of only 5-10 mm.
In larger ones, and these are coils, bitinia, zebrafish, the size is even larger. Toothless and barley can grow up to 25 cm.
How do mollusks move
“Snails”, “shells” - all these mollusks can move, that is, move, crawl both along the bottom and along aquatic vegetation. they have a very muscular leg (a kind of triangle of muscles), with the help of which they can move tens of meters, leaving behind a characteristic trace - a path.
Who eats shellfish
Almost all fish eat the most delicious shellfish meat, with the exception of the podust, a perephyton-sucker, probably this water cow, and the silver carp, a filter feeder. Not every fish is capable of reaching the fish to this delicacy, since the mollusk has strong armor - a “shell”. The strength of the armor is different - some are thicker, some are thinner. Soft, thin shells of peas and balls are able to gnaw through many fish, especially carp, bream, silver bream, and crucian love them. In reservoirs where there is little grass and a lot of fish, there are very few such mollusks, since they are eaten by everyone who is not lazy.
Coils and bitinia live easier: their shells are more massive and larger, it is more difficult for most fish to crush them. Large specimens of ide, bream, and roach easily cope with them. Large whitefish are very fond of bitinia and can eat a couple of hundred shells during the day. The roach is very fond of the zebrafish shell, which is the only one of its kind to eat them. Barley shell, toothless, not every fish can crush.
Catfish, large bream, carp - eat these large mollusks, which have not yet strengthened the shell. Adult toothless and barley fish are eaten only after their death, when the muscle-contactor is no longer active. In this case, the valves at the sink diverge and the fish is able to suck out the soft and tasty contents.
Trout and eel feed on small molluscs. Such a fish as a tench, with pleasure eats all kinds of living creatures that are found in water thickets. But due to the fact that his mouth is soft, he cannot crush a large shell, so he has to eat young mollusks. Most of all tench loves balls and coils.
Growing burbots and catfish eat mollusks often and with great pleasure. Having matured, they, of course, switch to feeding on fish, but they will not swim past a dead or crushed toothless, whose shell is open.
Black carp, having pharyngeal teeth like millstones, is a real thunderstorm of molluscs. He is able to crush almost any shell, as long as it fits in his mouth. Well, a large carp can put anything in its mouth ... Black carp easily copes with zebra mussel - which has a powerful shell.
shellfish are food for fish all year round, regardless of the season, but most of all in autumn. Autumn shellfish are much tastier than spring or summer ones. But it's not that. It turns out that the aquatic vegetation dies off and the shells have nowhere to hide, and accordingly it is easier for the fish to detect them. Much depends on the rhythm of nutrition of each type of fish. If at this time of the year the fish does not feed or feeds poorly, then it will not be happy with mollusks either.
What are the diseases of shellfish
Many have seen inky black spots ( diplostomosis) on fish such as roach, bream ... Intermediate hosts here are reels and fish, the final tree frogs and herons.
Tetracotylosis- here the causative agent of the disease must undergo development in the gastropod mollusk before infecting the fish.
And it turns out that our fish shellfish bring both benefit and harm.
Molluscum contagiosum is a viral skin disease in the form of multiple rounded rashes with a depression in the center. Mostly children are ill. Treatment most often does not require. Passes on its own.
ICD code 10: B08.1 - Molluscum contagiosum
Synonyms: epithelial mollusk, Bazin's pox-like acne, Neisser's contagious epithelioma, warty mollusk, candidal mollusk (erroneous name), Hebra's sebaceous mollusk.
Treatment: see a dermatologist.
Cause and mechanism of infection
The cause of molluscum contagiosum is a virus from the smallpox group, from the poxvirus family. In the international taxonomy of viruses, it is called Molluscum contagiosum virus: link.
- Only the person is sick. Animals don't get sick!
- Scientists have discovered several types of molluscum contagiosum virus.
- The source of the virus is skin formations in the patient.
- The virus is stable in the environment.
- The virus is transmitted by contact from a sick person (which is often in children's groups). Infection can also occur when using hygiene items or clothes of a sick person, in a pool, in a bathhouse, on the beach, etc.
- The incubation period (the period from infection to the appearance of symptoms on the skin) is from 2 weeks to 6 months.
- A predisposing factor to the disease: a decrease in general and / or local immunity in the skin. In HIV patients, molluscum contagiosum occurs very often (up to 15% of patients with HIV infection).
- Through microtrauma of the skin, scratching, the virus penetrates into the superficial cells of the skin epithelium (into the cells of the epidermis), integrates into them and begins to multiply. At the same time, the activity of immune cells in human skin is suppressed for a certain time, which also leads to the rapid development of the virus.
- Mostly children and adolescents are ill.
- In adults, when a mollusk appears on the body, one should look for the cause of a decrease in local or general immunity. It could be diabetes or atopic dermatitis. This may be chemotherapy for blood cancer (leukemia) or HIV infection. This may be aggressive antibiotic therapy or the use of ointments with corticosteroids.
- After treatment, the virus is not found in the human body. Immunity to him is unstable. Therefore, after a few years, a person can become infected again.
Why "contagious" and why "mollusk"?
Because under the microscope, the contents squeezed out of the skin formation look like a mollusk.
And “contagious” means contagious.
Symptoms and clinic
1) The main symptom of molluscum contagiosum: the appearance of many rounded formations on the skin.
These formations (papules) are 1 to 5 mm in size, spherical in shape with a depressed center. Also called - umbilical (from the word navel) or crater-shaped depression. Small formations in the initial stage do not yet have a depressed center and look like ordinary abscesses (see photo).
In the photo: it looks like a molluscum contagiosum
2) Itching almost never happens. There is also no pain.
3) Localization - the whole body: skin of the face, neck, torso, limbs. With the sexual route of infection - around the genitals, on the pubis, on the hips. Never occurs on the skin of the palms and soles of the feet.
4) The number of papules - from a few pieces to several hundred.
5) When pressing on the papule, a thick liquid and a curd mass in the center are released.
Attention: there should be no general reaction - no temperature, no headache, no weakness.
6) Atypical types of mollusks often appear, that is, unlike the classical form of education:
Diagnostics
With the classic form, the diagnosis of molluscum contagiosum is easy to make. It takes into account: children's age, the presence of children with molluscs in the team, multiple spherical formations on the skin with an umbilical depression.
Difficulties in diagnosis are rare, with atypical forms. But even with atypical species, dermatoscopy clearly shows umbilical depressions in the center of the mollusk papules.
This is what a mollusk looks like with dermatoscopy
In difficult cases, the doctor resorts to squeezing the papule with tweezers. If crumbly masses are squeezed out of the papule, with 99% probability it is a molluscum contagiosum.
In even rarer cases, they resort to diagnostics under a microscope. To do this, crumbly masses are sent to the laboratory, where a picture corresponding to this disease is determined under a microscope. At the same time, eosinophilic inclusions are found in the cytoplasm of cells.
Differential Diagnosis molluscum contagiosum is carried out with diseases:
- pyoderma (pustules on the skin),
- chickenpox (chickenpox),
- filiform papillomas (),
- vulgar warts (),
- genital warts on the genitals (),
- milia.
Molluscum contagiosum in adults - features
1) Both women and men are equally often ill.
2) Be sure to find out the predisposing factor to its appearance in adults. Why did he appear?
3) In adults, the frequent location of molluscum contagiosum is the genitals and inguinal region.
In women: on the pubis and labia. In men - on the penis and pubis. In this case, it has similarities both with the initial stage of genital warts, and with pustular diseases in the genital area. This arrangement is due to sexual transmission of infection.
4) In the treatment it is necessary to adjust common disease, which led to a decrease in immunity and activation of the virus:
- treatment diabetes,
- correction of dysbacteriosis,
- correction of drugs that depress the immune system (cytostatics, corticosteroids, including locally in the form of ointments)
treatment of HIV infection.
5) A variant is quite possible: a child caught a mollusk in a kindergarten - adults fell ill after that. All family members should be examined at once.
6) Treatment of pregnant women with molluscum contagiosum is different from other women: you should stop using antiviral and immune drugs, do not use cauterizing agents such as super celandine. The only treatment for pregnant women is the removal of molluscum papules.
Molluscum contagiosum in children
Most often, children under the age of 10 are sick. During this period, there is an active interaction of the child with the outside world, and the immune system familiar with many bacteria and viruses. In the same period, warts first appear in children, during this period, children suffer from childhood infections.
Is it necessary to treat molluscum contagiosum in children and how?
Only with a clear cosmetic defect and with complications. Treatment methods are described below.
On the face, remove the education tool with extreme caution so as not to lead to subsequent scarring.
Treatment in children and adults
In children and most adults, untreated, the symptoms of molluscum contagiosum go away on their own once antiviral immunity is established. Term - in 4-6 months, sometimes 1-2 years.
It is possible to treat mollusks on the body only for medical reasons: trauma, inflammation. Cosmetic indications - exclusively at the request of the patient.
Directions for the treatment of molluscum contagiosum:
1) Removal of formations
2) Local treatment
3) General treatment
4) Treatment of complications (inflammation, allergies, skin ulceration)
Molluscum Removal
According to most dermatologists, the removal of skin rashes is by far the most effective treatment for skin molluscs.
1) Removal with tweezers or a surgical spoon (curette)
- Previously, the doctor performs local anesthesia of the skin with Emla cream or another surface anesthetic.
- The doctor squeezes the jaws of the tweezers and squeezes out the contents of the papule (as in the video below). If necessary, the resulting small cavity is also scraped out with tweezers or exfoliated with a curette (Volkmann's sharp spoon).
If the papules are small, then no scraping is needed. - After that, the doctor carefully removes the curdled masses and cauterizes the resulting wound with 3% hydrogen peroxide and tincture of iodine.
- Some patients at home perform self-opening of mollusk papules with a needle, as in this video.
We remind you that it is not recommended to do it yourself. Wiping the skin with a napkin, thereby spreading and rubbing the viruses into neighboring areas of the skin, you thereby only spread the infection even further. - After removing the mollusk, the wound must be treated with iodine or brilliant green once a day for another 3 days.
- With proper removal of elements of molluscum contagiosum, no scars remain on the skin.
2) Electrocoagulation
The doctor cauterizes the papule with an electrocoagulator (electric knife). Subsequently, after such treatment, scars may remain.
3) Liquid nitrogen (cryolysis) -
The doctor cauterizes the papule with liquid nitrogen. Cells with the virus are frozen and die. With proper cryodestruction, there are no scars on the skin. But the procedure can be painful.
4) Laser -
The doctor vaporizes the molluscum papule with a laser beam. It also doesn't leave scars.
Local treatment
Antiviral creams and ointments are used:
- viferon ointment,
- 3% oxolinic ointment,
- 1% gel viru-merz serol,
- Infagel,
- Ointment acyclovir,
- Virolex ointment,
- Gripferon spray.
General treatment
Stimulation of general immunity and antiviral drugs.
- isoprinosine tablets ()
- viferon in candles,
- polyoxidonium in candles,
- anaferon for children in tablets,
- other interferon preparations.
Treatment of complications
A complex of drugs is used to relieve complications:
- antibiotic ointments - for the treatment of bacterial inflammation,
- antihistamines to reduce an allergic skin reaction.
Folk methods at home
Folk remedies against molluscum contagiosum are ineffective. Therefore, they cannot be recommended by a dermatologist for the treatment of this disease in either children or adults.
Remember: the cause of the mollusk is a virus, a predisposing factor is a decrease in immunity.
Therefore, from folk methods general immunity-strengthening techniques and antiviral agents should be used.
1) Increase immunity by natural methods.
2) Antiviral plants.
- Garlic.
Crush a clove of garlic in a garlic press and put it on the papules for a few minutes. There will be a slight sting.
Apply 3-4 times a day also during the entire period of rashes.
You can not apply, but simply lubricate the skin. - Lubrication of papules with a solution of potassium permanganate, fucorcin, an alcohol solution of iodine or brilliant green.
An ineffective method, since such antiseptics have practically no effect on the molluscum contagiosum virus. The only use of such solutions is to lubricate wounds at home after removing the mollusks with tweezers or a curette. - Celandine. Celandine juice is poisonous, has antiviral and antitumor effects.
Mollusks are smeared with celandine juice 3-4 times a day throughout the entire period of skin rashes. - Lubrication of papules with juice from bird cherry leaves, infusion of succession, calendula - these folk remedies have a very weak effect.
- Super cleaner, molustin and molutrex.
In Russia, a lotion called Molyustin is sold. The drug is not a drug. This is a mixture of plant extracts + potassium alkali. Causes a chemical burn of the skin, as a result of which the papules of the mollusk die off. Efficiency in molluscum contagiosum is low.MOLUTREX is the French analogue of molustin. In fact, MOLUTREX is pure potassium hydroxide, without additives, that is, caustic alkali, the French analogue of Super celandine. Causes chemical skin burns. Does not work on viruses.
Super celandine is a completely different drug than the herb celandine. This is a set of alkalis. It leads to a chemical burn of the skin, as a result of which the papules of the mollusk die off.
When treating at home with super celandine, molutrex and molustin, you should be extremely careful not to cause a deep skin burn and scarring afterwards. You can not use cauterizing preparations to remove mollusks on the face, on the labia in women and the penis in men.
- strengthening the immune system naturally,
- you can not take a hot bath - you can only shower,
- you can’t rub the body with a washcloth - soap yourself only with your hands,
- you can not rub the body with a towel - just blot,
- you can’t open skin papules yourself, so as not to spread the infection to other areas of the skin,
- a patient with molluscs on the body should be provided with separate personal hygiene items and bed linen. Wash his clothes separately. Thoroughly steam the laundry with an iron,
- always use only personal hygiene items!
Prevention
The main thing that should be applied constantly is the prevention of molluscum contagiosum.
Attention: if the doctor did not answer your question, then the answer is already on the pages of the site. Use the search on the site.
Molluscum contagiosum is one of the infectious diseases that can manifest itself in the form of rashes in the genital area, in the lower abdomen, on the pubis and thighs. Erythematous formations have a characteristic shape, they are small, dense in consistency, with a slightly shiny surface.
The molluscum contagiosum virus, considered the causative agent of the disease, belongs to smallpox viruses. In its purified form, it has an oval or rectangular shape, the size of the pathogen reaches 230–330 nm. In very thin sections of infected cells, inclusion bodies are located in compartments that are formed by thin walls. The space between the partitions is occupied by nests of mature particles of the pathogen. The cytoplasm around the cavities resembles a honeycomb and is divided into larger spherical honeycombs compared to viral particles. Molluscum contagiosum has a cytopathic effect at the level of human cells, but does not multiply in tissue cultures in serial passages.
Symptoms of molluscum contagiosum on the genitals may appear 14-15 days after the virus enters the human body. A case is described when the disease first made itself felt seven months after the tattoo was applied to the skin. The first signs of molluscum contagiosum, which patients can notice on their own, are pinhead-sized nodules with a dense texture. Over time, rashes become massive, while the skin does not undergo any changes.
Patients, as a rule, do not note any subjective sensations. In the central part of each growth there is a small depression with a hole. With a slight pressure on the papule, a white flaky mass is released, which consists of the ovoid bodies of the pathogen, also called molluscs.
Examination of the patient and carrying out laboratory research. The characteristic signs of the disease are considered to be a sharp border between the nodule and healthy skin, the absence of inflammation, and an umbilical depression in the central part of the formation. A diagnostic sign is also a liquid in the form of a white slurry, which flows out when the papule is squeezed.
When examining the contents of the vesicles under a microscope, you can see the dead cells of the epidermis and many ovoid bodies.
In some cases, treatment is carried out using diathermocoagulation or electrolysis. If the rashes are massive, then patients are prescribed tetracycline antibiotics.
shellfish
The structure of molluscs. All molluscs can be given the following characteristic: they are secondary cavities and have salient feature structures - bilateral symmetry of the body. However, in some groups, the symmetry of the body may be violated for the second time due to uneven growth or displacement of organs. For example, this happens in gastropods due to the presence of a turbospiral shell. The body can be roughly divided into a non-segmented trunk, head, and leg. On the dorsal side, many of them have a shell, while some of them are absent or poorly developed. On the head are tentacles, mouth, eyes. In representatives of the class of bivalves, the head is secondarily reduced. The organ of movement is the leg - a muscular unpaired formation of the abdominal part of the body. In the inhabitants of water bodies, the leg can be transformed into a swimming organ, in some species it is completely lost. The trunk is an visceral sac with internal organs, covered on the outside with a mantle - a fold of skin. The mantle takes part in the creation of the shell. In the mantle cavity, formed directly by the mantle and the body, there are respiratory organs, sensory organs, and the ducts of the reproductive and excretory systems and the anus also open into this cavity.
Nutrition shellfish. Nutrition of terrestrial mollusks - plant food, marine - plankton, bacteria, small plants. Many are exclusively herbivores. Sedentary organisms from the class of bivalves are filter feeders by the mechanism of obtaining food by filtering water through the gills, followed by the movement of settling particles into the oral cavity. Digestive system It is represented by a through intestine, consisting of three parts: anterior, middle (stomach) and posterior, ending with an anus. Mollusks have a paired digestive gland called the "liver". Breathing is carried out through ctenidia (the prototype of the gills), and in terrestrial forms the mantle cavity turns into a lung. The circulatory system is open, the heart consists of one ventricle and has from one to four atria in different types. The nervous system is represented by a near-pharyngeal nerve ring and several paired nerve nodes - ganglia. The excretory system consists of two kidneys.
reproduction shellfish. Some species of molluscs are dioecious, but there are also hermaphrodites. A larva or a formed mollusk emerges from a fertilized egg in lower forms, rare higher forms are viviparous.
Molluscum contagiosum: prevention and treatment
What is molluscum contagiosum?
Molluscum contagiosum is a viral skin infection. Most often it is observed in children, especially preschool age, as well as in adults with reduced immunity.
How can you get molluscum contagiosum?
1) by contact - when the skin comes into contact with the affected skin (direct contact) or the skin with a contaminated surface (when using common hygiene items - a household way). Through contaminated toys, bedding, underwear, washcloths, towels, etc. used by a child whose skin has already developed molluscum contagiosum, these are the most characteristic ways of transmitting this disease in children. This method of infection is also characteristic of adults. Also, the mollusk is easily transmitted from a surface contaminated with the virus - you can get infected in a bath, sauna, pool and other similar public places.
The first 2 weeks, and sometimes several months, the mollusk that has fallen on the skin or mucous membrane does not manifest itself in any way. Then, after a period of latent form, the disease enters the active phase. On the skin, first appear single, then multiple painless rounded dense nodules with an impression in the center.
Appearance of molluscum contagiosum
The color of the rash can vary from normal skin color to pink, sometimes with a waxy or pearly tint. The size of the nodules can be different - from millet grain to a pea (from 1 mm to 15 mm), in rare cases, as a result of the fusion of several nodules, giant molluscum contagiosum can form.
When pressed with tweezers, a white mushy mass is released from the nodule, in which, in addition to keratinized cells, there are many mollusc-like bodies.
Subjective sensations are absent, but sometimes a feeling of itching appears in the area of the nodules. It is possible to attach a secondary bacterial infection with an inflammatory reaction.
What areas of the skin are most commonly affected by molluscum contagiosum?
Most often, rashes are located on the face, neck, hands, torso, and abdomen.
In children, molluscum contagiosum may affect any area of the skin, more often on the skin of the hands, face, neck, except for the palms and soles.
In adults, molluscum contagiosum is more common on the skin of the anterior abdominal wall, thighs, perineum, and external genitalia.
Molluscum contagiosum prevention
Molluscum contagiosum is more common in children and adults with weakened immune systems. To prevent the manifestation of the disease, it is necessary to increase the body's resistance - lead a healthy lifestyle, take vitamins. In winter, when the body is most weakened, it is necessary to prescribe immunostimulants - consult your doctor.
Children are especially susceptible to infection with molluscum contagiosum. It is necessary to regularly examine the child's skin: molluscum contagiosum is very quickly transmitted in children's groups from the sick to the healthy. It is much easier to deal with the disease detected at an early stage. In addition, the detection of the disease will prevent infection of other children. To prevent the spread of infection, it is necessary to isolate a sick child from an organized team, to conduct preventive examinations of children in preschool children's institutions and schools.
Prevention of molluscum contagiosum is to follow the rules of personal hygiene. See a dermatologist as soon as possible if unusual rashes, redness, peeling, itching, etc. appear. This will help identify other unpleasant diseases, such as fungus, allergies, or contract dermatitis.
Molluscum contagiosum treatment
Although molluscum contagiosum most often does not cause pain, treatment is still necessary, mainly because of its contagiousness. When attached to the nodules caused by the molluscum secondary infection, severe inflammation of the surrounding tissues can occur. With the advanced form of molluscum contagiosum, a generalized infection can be observed - when rashes begin to appear throughout the body. This condition is especially characteristic of HIV-infected people.
Try not to damage the molluscum contagiosum - infectivity in this case increases dramatically. After damage to the mollusk, it must be removed, and the wound should be cauterized, for example, with brilliant green or iodine.
At the moment, molluscum contagiosum is treated by removing the nodules, followed by the appointment of a course of antiviral and immunostimulating agents.
Molluscum contagiosum is removed by a dermatologist on an outpatient basis. Each element of the molluscum contagiosum is removed with tweezers, or scraped out with a sharp Volkmann spoon, followed by lubrication of the lesions with an alcohol solution of iodine, a saturated solution of potassium permanganate.
Removal of molluscum contagiosum can also be carried out using a laser - this method may be most appropriate when the molluscum is located on the face, neck, arms and other exposed parts of the body. When removed by a laser, healthy tissues surrounding the mollusk are not disturbed, healing is faster, and there are no scars. Methods such as diathermocoagulation, cryotherapy can also be used.
Within 4 days after the procedure for removing the mollusk, it is necessary to lubricate the affected area with iodine once a day. Lubrication of wounds with Viferon ointment gives good results. After removal, the mollusk may appear for some time. It is necessary to remove new rashes until they completely disappear. To prevent recurrence, the remaining wounds are lubricated with antiviral ointments such as viferon ointment or cycloferon liniment (improve local immunity), acyclovir ointment, etc.
Particular attention should be paid to activities after the removal of the mollusk. This is the treatment with disinfectant solutions of things for the individual use of the sick person, boiling bed and underwear, clothes. Since there is also a household route of transmission of the infection, the use of the patient's linen, bed and bathroom by other uninfected family members should be avoided. For the same reason, when a virus is detected in one family member, it is recommended to examine the rest, and first of all the person with whom the patient is in an intimate relationship. Only after the symptoms of molluscum contagiosum disappear can a person return to sexual activity.
For local drug treatment of molluscs, you can use
Imiquimod is an immune response modifier. When applied to the skin, imiquimod increases the production of antiviral and antitumor agents - interferon alfa and tumor necrosis factor. According to the description given by the manufacturer, as well as according to a number of clinical trials, imiquimod allows you to get rid of the manifestations of molluscum contagiosum in 8-10 weeks of use. A serious factor limiting the use of the drug can be considered to be used only in adults (strictly contraindicated for children), high cost for a small amount of cream, as well as the need for long-term use.
Imiquimod is part of such preparations as Aldara cream (manufacturer 3M Health Care Limited (UK), Imiquimod cream 5% - generic Aldara company Nycomed (Denmark), Imiquad cream 5% (manufacturer Glenmark Pharmaceuticals India).
Antiviral, immunomodulatory, antitumor, antiproliferative. Prevents viral infection of cells, changes properties cell membrane, prevents adhesion and penetration of the virus into the cell. Initiates the synthesis of a number of specific enzymes, disrupts the synthesis of viral RNA and viral proteins in the cell. Trade name: Viferon (instruction here), Infagel ointment (instruction here), etc.
It has a wide range of pharmacological activity: antiviral, immunocorrective, anti-inflammatory. Trade name of meglumine acridocetate Cycloferon. Instructions for the drug Cycloferon liniment here.
The type of molluscs includes invertebrate coelomic animals with bilateral symmetry. This type includes two subtypes (lateral nerve and testate), divided into seven classes: gastropods, cephalopods, spadefoots, bivalves, armored, solenogasters, pit-tails. 98% of mollusk species are included in the two most extensive classes - Gastropods and Bivalves. The type unites more than 130 thousand species of animals that are distributed throughout our planet. In the course of evolution, molluscs appeared about 500 million years ago. Several classes are known from the Lower Cambrian. Many scientists agree that these organisms evolved from primary coelomic animals. This is their common ancestor annelids with which molluscs have common features buildings. Habitat - seas, fresh water. Some of them live on land in a humid environment.
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The virus is transmitted sexually or by household means (with household or hygiene items when they are shared with a sick person). Infection can occur in the pool, children's team. The disease occurs in all countries of the world in a sporadic or epidemiological form.
Symptoms of molluscum contagiosum on the genitals
Papules are painless, hemispherical in shape, in some cases slightly flattened. The formations have the color of healthy skin or a pinkish tint, they can be located individually or in groups.
According to the results of histological examination, separate inclusions are formed in the basal layer of the skin. Over time, increasing in size, they completely fill the cell, pushing the nucleus to the side.
In some cases, the formations can merge with each other, forming a giant mollusk, in the central part of the nodule, an ulceration similar to an epithelioma is observed. In differential diagnosis, the contents of the papule are studied, squeezing it from the sides. The mass, typical for molluscum contagiosum, is white and mushy in consistency, which is not characteristic of epithelioma. In addition, rashes caused by molluscum contagiosum must be distinguished from the symptoms of smallpox, pustular syphilis, etc.
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Treatment of molluscum contagiosum on the genitals
Treatment of molluscum contagiosum in the genital area can be carried out by scraping individual formations with a special sharp spoon. At the same time, the contents of the papules are squeezed out with tweezers, and the place of manipulation after the end of the procedure is treated with iodine.
In order to prevent molluscum contagiosum on the genitals, both sexual partners are treated. Until the symptoms of the disease are completely eliminated, patients are advised to refrain from sexual intercourse, not to use common household items, bed linen etc. Treatment should be carried out under medical supervision until recovery.
Molluscum contagiosum - photo, causes and symptoms (in children, in adults), diagnosis and treatment. Methods for removing molluscum contagiosum on the skin of the face, on the eyelid, on the genitals, etc.
molluscum contagiosum is an infectious dermatosis caused by a virus of the smallpox family, and manifested by the formation of small dense nodules on the skin with an umbilical depression in the center. The disease is quite widespread among children and adults, as it is transmitted by contact and sexually. The disease is usually self-healing within 6 to 24 months, and therefore it does not always require treatment. Molluscum contagiosum is not a health hazard. but creates visible cosmetic defects, which many people want to get rid of with the help of treatment, without waiting for the rash to go away on their own.
General characteristics of the disease
Molluscum contagiosum is also called contagious shellfish. molluscum epitheliale or epithelioma contagiosum. The disease is viral infection. in which the skin is affected. The virus enters the cells of the basal layer of the epidermis and causes an accelerated division of cellular structures, as a result of which small round-shaped growths-nodules with an umbilical depression in the center form on the surface of the skin. A recess in the central part of the nodule is formed due to the destruction of epidermal cells. The growths themselves contain viral particles and a large number of randomly located epidermal cells.
Molluscum contagiosum is a benign disease, and does not apply to tumor formations. since the formation and growth of nodules is due to the effect of the virus on a specific small area of \u200b\u200bthe skin. There is no inflammatory process in the epidermis in the growth zones of molluscum contagiosum nodules.
Molluscum contagiosum is quite widespread in the population, and people of any age and gender get sick. However, most often the infection occurs in children 2 to 6 years old, adolescents and people over 60 years of age. Children under one year of age almost never become infected with molluscum contagiosum, most likely due to the presence of maternal antibodies. transmitted to the baby through the placenta during fetal development.
Most at risk of infection molluscum contagiosum in immunocompromised people. for example, HIV-infected, cancer patients, allergic people, suffering from rheumatoid arthritis and taking cytostatics or glucocorticoid hormones. In addition, there is a high risk of infection in those who are constantly in contact with the skin of a large number of people, for example, massage therapists, nurses, doctors, nurses in hospitals and clinics, pool trainers, bath attendants, etc.
Molluscum contagiosum is ubiquitous, that is, in any country and climate zone, infection with this infection is possible. Moreover, in regions with a hot and humid climate, as well as with a low level of daily household hygiene, epidemics and outbreaks of molluscum contagiosum are even recorded.
The disease is caused orthopoxvirus. which belongs to the family Poxviridae, the subfamily Chordopoxviridae and the genus Molluscipoxvirus. This virus is related to variola, chickenpox and vaccinia viruses. Currently, 4 varieties of orthopoxvirus have been isolated (MCV-1, MCV-2, MCV-3, MCV-4), but molluscum contagiosum is most often caused by viruses of types 1 and 2 (MCV-1, MCV-2).
Molluscum contagiosum virus is transmitted from a sick person to a healthy person through close contact (skin to skin), as well as indirectly through the use of common household items, such as shower accessories, underwear, dishes, toys, etc. In adults, infection with molluscum contagiosum, as a rule, occurs sexually, while the virus infects a healthy partner not through the secrets of the genital organs, but through close contact of the bodies. That is why, in adults, molluscum contagiosum nodules are very often located in the groin, on the lower abdomen, in the perineum, and also on the inner thighs.
However, it has now been established that many people, even when infected, do not get sick with molluscum contagiosum, which is due to the functioning of the immune system, which does not allow the virus to multiply, but suppresses and destroys it, preventing the infection from moving into an active course.
From the moment the molluscum contagiosum virus enters the skin of a healthy person until nodules appear, it takes from 2 weeks to six months. Respectively, incubation period infection ranges from 14 days to 6 months.
After the end of the incubation period, the disease enters the active stage, in which tight raised nodules spherical or oval shape and various sizes - from 1 to 10 mm in diameter. Sometimes nodules merging with each other can form giant plaques up to 3–5 cm in diameter. Nodules of molluscum contagiosum are dense, shiny, painted in pearly white, pink or gray-yellow. Some nodules may have an umbilical depression in the center, colored red-pink. However, such impressions are usually present not in all nodules, but only in 10-15%. When pressing on the nodule with tweezers, a white mushy mass comes out of it, which is a mixture of dead epidermal cells and viral particles.
The nodules slowly increase in size, reaching a maximum in 6 to 12 weeks after the appearance. After this, the formations do not grow, but gradually die off, as a result of which they disappear on their own after 3 to 6 months.
The number of rashes can be different - from single nodules to numerous papules. Due to the fact that self-infection is possible, the number of nodules may increase over time, since the person himself spreads the virus over the skin.
Usually, molluscum contagiosum nodules are concentrated on any one limited area of the skin, and not scattered throughout the body, for example, in the armpits, on the abdomen, on the face, in the groin, etc. Most often, nodules are localized on the neck, trunk, armpits, face and genital area. In rare cases, elements of molluscum contagiosum are localized on the scalp, soles, on the skin of the lips, tongue, mucous membrane of the cheeks.
Diagnostics molluscum contagiosum is not difficult, since the characteristic appearance of the nodules allows you to recognize the disease without using any additional techniques.
Treatment molluscum contagiosum is not carried out in all cases, since usually within 6 to 9 months the nodules disappear on their own and no longer form. In rare cases, self-healing is delayed for a period of 3 to 4 years. However, if a person wants to get rid of the nodules without waiting for self-healing, then the formations are removed in various ways (mechanical scraping with a Volkmann spoon, cauterization with a laser, liquid nitrogen, electric current, etc.). Usually, the removal of molluscum contagiosum nodules is recommended for adults so that they do not serve as a source of infection for others. But in the case of a disease in children, dermatovenereologists most often recommend not to treat the infection, but to wait until the nodules pass on their own, because any procedure for removing formations is stressful for the child.
Molluscum contagiosum - photo
Photo of molluscum contagiosum in children.
Photo of molluscum contagiosum in men.
Photo of molluscum contagiosum in women.
Causes of the disease (molluscum contagiosum virus)
The cause of molluscum contagiosum is a pathogenic microorganism - orthopoxvirus from the family Poxviridae of the genus Molluscipoxvirus. This virus is ubiquitous, and affects people of any age and gender, as a result of which the population of all countries suffers from molluscum contagiosum.
Currently, 4 varieties of orthopoxvirus are known, which are designated by Latin abbreviations - MCV-1, MCV-2, MCV-3 and MCV-4. The cause of molluscum contagiosum in countries former USSR most often are viruses of the first and second types - MCV-1 and MCV-2. Moreover, in children, molluscum contagiosum, as a rule, is provoked by type 1 orthopoxvirus (MCV-1), and in adults by type 2 virus (MCV-2). This situation is due to the fact that the type 1 virus is transmitted mainly by contact and indirectly, through common objects, and the type 2 virus is transmitted through sexual contact. However, all types of virus cause the same clinical manifestations.
Ways of transmission of infection
Molluscum contagiosum is transmitted only from person to person, since animals do not suffer from this infectious disease and are not virus carriers.
Transmission of the molluscum contagiosum virus occurs from a sick person to healthy contact-household, mediated by contact, sexually and through water. Contact household way transmission consists in infecting a healthy person through touching the skin of a child or adult suffering from molluscum contagiosum. Accordingly, any tactile contact (eg, hugging, shaking hands, cuddling closely during rush hours on public transport, massages, wrestling, boxing, breastfeeding, etc.) with a person with molluscum contagiosum can lead to infection with this infection of any healthy person, regardless of age and gender.
mediated contact path molluscum contagiosum transmission is the most common and consists in infecting healthy people through touching general subjects household items that have retained viral particles after being used by a person suffering from an infection. That is, infection can occur through toys, cutlery, dishes, bedding and underwear, carpets, furniture upholstery, towels, washcloths, razors and any other items that a person suffering from molluscum contagiosum has come into contact with. Due to the possibility of indirect infection in close groups, especially children, outbreaks of the disease occur episodically, when almost the entire group becomes infected.
Sexual way transmission of molluscum contagiosum is typical only for adults who have unprotected sex (without a condom). With this transmission route, the nodules are always located in the immediate vicinity or in the genital area.
Waterway transmission can be conditionally attributed to indirect-contact, because in this case, a person suffering from molluscum contagiosum introduces viral particles into the aquatic environment, which can be “picked up” by any other person in contact with the same water. This route of transmission makes it possible to become infected with molluscum contagiosum when visiting pools and baths. saunas, water attractions, etc.
In addition, a person who already has molluscum contagiosum may autoinfection through friction and scratching of the skin.
Regardless of the route of transmission, the course and clinical manifestations of molluscum contagiosum are always the same.
Not all cases of exposure to the virus result in infection, as some people are immune to this infection. That is, even if a person who is immune to molluscum contagiosum comes into contact with the virus, he will not become infected, and the infection will not develop in him. All other people who come into contact with the virus become infected and develop clinical signs.
The most vulnerable and susceptible to infection with molluscum contagiosum are people with a reduced activity of the immune system, such as, for example, HIV-infected people taking glucocorticoid hormones. persons over 60, etc.
Molluscum contagiosum - symptoms
The course of the disease
From the moment of infection with molluscum contagiosum to the first appearance of clinical symptoms, it takes from 2 to 24 weeks. After the end of the incubation period, small, dense, painless nodules 1 to 3 mm in diameter appear on the area of the skin where the molluscum contagiosum virus has invaded. These nodules slowly increase in size up to 2-10 mm in diameter within 6-12 weeks, after which they disappear on their own within 6-12 weeks. In total, from the moment the first nodules appear to their complete disappearance takes an average of 12 - 18 weeks, but in some cases the disease can proceed much longer - from 2 to 5 years. After recovery from molluscum contagiosum, lifelong immunity is developed, so re-infection occurs only in exceptional cases.
However, until all the nodules on the skin have disappeared, self-infection is possible when combing or rubbing the affected skin against healthy ones. In this case, new nodules of molluscum contagiosum appear on the newly infected area of the skin, which will also grow within 6-12 weeks, after which they will involute on their own for 12-18 weeks. Accordingly, the approximate period of self-healing must be counted by adding 18 months to the date of the appearance of the last nodule.
Molluscum contagiosum is a benign disease that tends to go away on its own, without any special treatment, once the body's own immune system suppresses the activity of the virus. Rashes, as a rule, do not bother a person, because they do not hurt or itch, but for the most part they are only a cosmetic problem. In addition, the virus does not spread through the blood or lymph through the body and does not affect other organs and systems, as a result of which molluscum contagiosum is a safe disease, which most often for this reason is recommended not to be treated with special means, but simply wait until your own immunity kills the virus and, accordingly, the nodules will not disappear.
However, people are often unwilling to wait for molluscum contagiosum nodules to go away on their own, but are willing to remove them for cosmetic reasons, or to avoid being a source of infection to others. In such cases, you need to be mentally prepared for the fact that after the removal of existing nodules, new ones will appear, since only the process of destroying the rash does not affect the activity of the virus in the thickness of the skin, and until your own immune system suppresses it, the pathogen can cause the formation of nodules again and again.
After the self-disappearance of molluscum contagiosum nodules, there are no traces left on the skin - scars or scars, and only in rare cases can small areas of depigmentation form. If the nodules of the molluscum contagiosum were removed by various methods, then small and inconspicuous scars may form at the site of their localization.
Sometimes the skin around the nodules of molluscum contagiosum becomes inflamed, in which case topical application of antibiotic ointments is necessary. The appearance of a nodule on the eyelid is a problem and an indication for its removal, since the growth of the formation can lead to visual impairment and loss of eyelash hair follicles.
If a person develops molluscum contagiosum nodules in large numbers, in different parts of the body or are very large (more than 10 mm in diameter), then this may indicate immunodeficiency. In such cases, it is recommended to contact an immunologist to correct the immune status.
Molluscum contagiosum symptoms
The main and only symptom of molluscum contagiosum that can be seen with the naked eye is characteristic nodules protruding above the surface of the skin. Nodules can be localized on any part of the skin, but most often the formations form on the face, neck, upper part chest, in the armpits, on the hands and forearms, on the lower abdomen, inner thighs, pubis, around the anus and on the skin in the genital area. However, despite the wide range of localization options for molluscum contagiosum nodules, as a rule, all formations are always grouped in only one area of the skin. For example, nodules can be located on the neck, on the face, or on the abdomen, but all the formations are grouped in only one area and are absent on other parts of the body. Moreover, usually all nodules of molluscum contagiosum are located on the area of the skin into which the infection virus has penetrated. In rare cases, nodules can be randomly located on the entire surface of the body.
Nodules do not appear one at a time and gradually, but almost simultaneously, several formations are formed, which begin to grow slowly. As a rule, from 5 to 10 nodules appear, but in some cases their number can reach several dozen.
At the time of appearance, the nodules are small, 1–2 mm in diameter, but within 6–12 weeks they grow to 2–10 mm. Sometimes some elements can grow up to 15 mm in diameter, and usually there are nodules on the skin of different sizes, but the same appearance. If the formations of molluscum contagiosum are located close to each other, then they can merge, forming one giant bumpy surface up to 5 cm in diameter. Such giant nodes can become inflamed and suppurate, as a result of which crusts and ulcers form on their surface.
At any stage of growth, the nodules protrude above the surface of the skin, have a hemispherical and slightly flattened top shape, smooth edges, a dense texture, and are painted in white-pearl or pale pink. Moreover, at the beginning of the disease, the formations have the shape of a dome, a very dense texture and color slightly lighter than the surrounding skin, and over time they become soft, take the form of a semicircle, and the color may change to pinkish. Often the nodules may have a waxy sheen. A few weeks after the appearance in the central part of the formations, a depression similar to the navel appears. When the nodules are squeezed from the sides, a white mushy mass containing dead epidermal cells and viral particles is released from the umbilical opening.
The nodules have a smooth surface and are slightly different in color from the surrounding skin. The skin around the formations is usually unchanged, but sometimes an inflammatory rim is fixed around the perimeter of the nodules. The formations do not bother a person, because they do not hurt, do not itch, and, in principle, may not be noticed at all if they are localized in areas of the skin that are usually covered by clothing and are not visible. In rare cases, the nodules may occasionally itch. At these moments, it is very important to restrain yourself and not scratch the formations, since scratching and traumatizing the nodules can lead to the subsequent transfer of the virus to other areas of the skin. In such situations, self-infection occurs, and elements of molluscum contagiosum are formed on another area of the skin into which the virus has been introduced. It must be remembered that until the disappearance of the last nodule, molluscum contagiosum remains infectious.
With the localization of nodules on the eyelids, molluscum contagiosum can lead to conjunctivitis.
The described clinical picture of molluscum contagiosum is a classic form of infection. However, in addition to this, the disease can occur in the following atypical forms that differ from the classical morphological features nodules:
Regardless of the form of molluscum contagiosum, the course of infection is the same, and the differences relate only to the morphological characteristics of the nodules.
Molluscum contagiosum: characteristics of the rash, infection, incubation period, symptoms, quarantine, consequences (opinion of a dermatovenereologist) - video
Molluscum contagiosum in children
About 80% of cases of molluscum contagiosum are recorded in children under 15 years of age. Thus, it can be said that children are more susceptible to infection compared to adults. Most often, molluscum contagiosum affects children aged 1 to 4 years. Until the age of one, children almost never get infected, because, as scientists suggest, they are protected by maternal antibodies obtained during fetal development. In addition, it is known that children suffering from eczema are most at risk of infection. atopic dermatitis or taking glucocorticoid hormones for the treatment of any other disease.
Most often, children become infected with molluscum contagiosum when visiting the pool and playing those sports. which involve close tactile contacts and body contact with each other (for example, wrestling, boxing, etc.).
Symptoms and course molluscum contagiosum in children are exactly the same as in adults. However, due to weak volitional control of their desires, children can often comb molluscum contagiosum nodules and, thereby, become self-infected, transferring the virus to other areas of the skin, which leads to the constant appearance of new foci of rashes and prolongs the course of the disease. In addition, scratching the nodules can lead to their inflammation and the addition of a secondary infection that requires antibiotic treatment.
In children, nodules can be localized anywhere on the body, but are most often fixed on the chest, abdomen, arms, legs, armpits, groin, and genitals. The location of the formations in the genital area does not necessarily mean that the child became infected during sexual contact. The kid could simply get the molluscum contagiosum virus on his fingers from a sick person, and then scratch the skin in the genital area, as a result of which infection occurred precisely in this area of the skin.
Diagnostics molluscum contagiosum in children is not difficult, since the nodules have a characteristic appearance. Therefore, a dermatologist will make a diagnosis based on a simple examination of the formations. In some cases, when the dermatologist has doubts, he may take a biopsy or scraping from the nodule to study its structure under a microscope.
Treatment molluscum contagiosum in children is usually not carried out, because after 3 months - 4 years, all nodules disappear on their own, that is, self-healing occurs as a result of the immune system suppressing the activity of the virus. Therefore, given the fact that the molluscum contagiosum heals itself after a while, so as not to cause discomfort to the child, nodules are not removed. However, in some cases, doctors recommend removing nodules on the skin of children, as they constantly comb them and self-infect, as a result of which the disease flows for a very long time. In such situations, the nodules are removed mechanically, by freezing with liquid nitrogen, or using formulations containing substances to eliminate warts. such as salicylic acid. tretinoin, cantharidin, or benzoyl peroxide.
Although there are various methods for removing molluscum contagiosum nodules, doctors prefer not to use them in children, since all these methods will only help eliminate the formations, but will not prevent their reappearance, as long as the virus in the skin is active and not suppressed by the child's own immune system. In addition, any method can lead to the formation of scars, scars, burns or foci of depigmentation at the site of localization of nodules. And when the nodules pass on their own, scars or scars never form at the site of their localization, only sometimes foci of depigmentation can remain.
For the fastest possible self-healing of molluscum contagiosum in children, the following rules must be observed:
Molluscum contagiosum in women
The clinical picture, causative factors, course and principles of treatment of molluscum contagiosum in women do not have any features compared to men or children. For the course of pregnancy. molluscum contagiosum also does not affect the growth and development of the fetus, so women who are carrying a child and become infected with the infection may not worry about the health of the unborn baby.
Features of the disease in men
Molluscum contagiosum in men, like in women, does not have any obvious features. The only feature that may be a hallmark of infection in men is the possibility of localization of nodules on the skin of the penis, which leads to difficulties in sexual intercourse. In women, molluscum contagiosum never affects the mucous membranes of the vagina, but can only be localized on the skin in the genital area. Of course, this also creates difficulties during sexual intercourse, but not as pronounced as with the localization of nodules on the penis.
Features of molluscum contagiosum of various localization
Molluscum contagiosum on the face. When localizing nodules on the face, it is recommended not to remove them, but to leave them and wait for self-healing, because if the formations disappear on their own, then there will be no traces and scars in their place that create cosmetic defects. If you remove the knots with any modern method, then there is a risk of scarring and scarring.
Molluscum contagiosum on the eyelid. If the nodule is localized on the eyelid, then it is recommended to remove it, because otherwise it can injure the mucous membrane of the eye and cause conjunctivitis or other more severe eye diseases.
Molluscum contagiosum on the genitals. If the nodules are localized near the genitals, in the anus or on the penis, then it is better to remove them in any way, without waiting for them to disappear on their own. This tactic is based on the fact that the location of the nodules on the genitals or in the genital area leads to their trauma during sexual intercourse, which, in turn, provokes infection of the partner and the spread of infection to other areas of the skin. As a result, nodules that appear on the genitals can spread very quickly throughout the body.
Diagnostics
Diagnosis of molluscum contagiosum is not difficult and, as a rule, is made on the basis of an examination by a dermatologist of characteristic nodules. In almost all cases, no additional diagnostic methods are required to confirm the diagnosis of molluscum contagiosum.
However, in some rather rare cases, when the doctor has doubts, additional examinations are carried out to confirm molluscum contagiosum. Such additional examinations consist in taking a small piece of the nodule and then examining it under a microscope. Microscopy of the nodule biopsy allows you to accurately determine what the nodule is and, accordingly, whether it is a manifestation of molluscum contagiosum or any other disease (for example, keratoacanthoma, syphilis, etc.).
Molluscum contagiosum nodules distinguish from the following superficially similar formations. also localized on the skin:
Which doctor should I contact with molluscum contagiosum?
With the development of molluscum contagiosum, one should refer to dermatologist (make an appointment). which diagnoses and treats this disease. If the dermatologist is unable to perform any necessary removal manipulations, he will refer the patient to another specialist, for example, surgeon (make an appointment). physiotherapist (sign up) etc.
Molluscum contagiosum - treatment
General principles of therapy
Currently, molluscum contagiosum, unless the nodules are localized not on the eyelids and not in the genital area, is recommended not to be treated at all, because after 3-18 months the immune system will be able to suppress the activity of the orthopoxvirus, and all formations will disappear on their own, without leaving any on the skin. or traces (scars, scars, etc.). The fact is that immunity is developed to the molluscum contagiosum virus, but this happens slowly, so the body does not need a week to heal itself from the infection, as is the case with SARS. and several months or even up to 2 - 5 years. And if you remove molluscum contagiosum nodules before they disappear on their own, then, firstly, you can leave scars on the skin, and secondly, this increases the risk of their reappearance, and even in large quantities, since the virus is still active. Therefore, given that self-healing always occurs, and it is only a matter of time, doctors recommend not treating molluscum contagiosum by removing the nodules, but simply waiting a bit until they disappear on their own.
The only situations when it is still recommended to remove molluscum contagiosum nodules are their localization on the genitals or on the eyelids, as well as the pronounced discomfort caused by education to a person. In other cases, it is better to leave the nodules and wait for them to disappear on their own after the suppression of the activity of the virus by the immune system.
However, if a person wants to remove the nodules, then this is done. Moreover, the reason for such a desire, as a rule, are aesthetic considerations.
To remove nodules of molluscum contagiosum, the following surgical methods are officially approved by the Ministries of Health of the CIS countries:
- Curettage (scraping out nodules with a curette or Volkmann's spoon);
- Cryodestruction (destruction of nodules with liquid nitrogen);
- Husking (removal of the core of the nodules with thin tweezers);
- Laser destruction (destruction of nodules CO 2 - laser);
- Electrocoagulation (destruction of nodules by electric current - “cauterization”).
In practice, in addition to the officially approved methods for removing molluscum contagiosum nodules, other methods are also used. These methods consist in exposing the nodules of the molluscum contagiosum to various chemicals in the composition of ointments and solutions that can destroy the structure of the formations. So, at present, ointments and solutions containing tretinoin, cantharidin, trichloroacetic acid, salicylic acid, imiquimod, podophyllotoxin, chlorophyllipt are used to remove nodules. fluorouracil. oxolin. benzoyl peroxide, as well as interferons alpha-2a and alpha 2b.
Such chemical methods for removing molluscs cannot be called folk methods, since they involve the use of drugs. as a result, they are considered to be informal, proven by practice, but not approved by the Ministries of Health. Since these methods, according to the reviews of doctors and patients, are quite effective and less traumatic compared to surgical methods for removing molluscum contagiosum nodules, we will also consider them in the subsection below.
Molluscum contagiosum removal
Consider the characteristics of surgical and informal conservative methods removal of molluscum contagiosum. But first we consider it necessary to indicate that any surgical methods for removing nodules are quite painful, as a result of which it is recommended to use local anesthetics for manipulations. The best anesthetizes the skin ointment EMLA 5%. Other anesthetics such as lidocaine. novocaine and others are ineffective.
Laser removal of molluscum contagiosum. The nodules are pinpointed with a CO 2 laser beam or a pulsed laser. To destroy formations, it is optimal to set the following parameters of the laser beam - wavelength 585 nm, frequency 0.5 - 1 Hz, spot diameter 3 - 7 mm, energy density 2 - 8 J / cm 2. pulse duration 250 - 450 ms. During the procedure, each nodule is irradiated with a laser, after which the skin is treated with a 5% alcohol solution of iodine. If, after a week after the procedure, the nodules are not covered with crusts and have not fallen off, then another session of laser irradiation of the formations is performed.
Laser therapy allows to achieve the destruction of 85 - 90% of nodules after the first session. Moreover, after the formations fall off, there are no noticeable scars and scars on the skin, which makes the method suitable for removing nodules for cosmetic reasons.
Removal of molluscum contagiosum with liquid nitrogen. Each nodule is exposed to liquid nitrogen for 6-20 seconds, after which the skin is treated with a 5% alcohol solution of iodine. If nodules remain after a week, then they are re-destroyed with liquid nitrogen.
This method is painful, and is not suitable for removing molluscum contagiosum nodules for cosmetic reasons, since after the destruction of formations with liquid nitrogen, blisters may appear on the skin, healing with the formation of scars and foci of depigmentation.
Removal of molluscum contagiosum by electrocoagulation. The method consists in "cauterization" of the nodules with an electric current, similar to the "cauterization" of cervical erosion. After the procedure, the skin is smeared with a 5% alcohol solution of iodine and the result is evaluated after a week. If the nodules have not fallen off, then they are “cauterized” again.
Removal of molluscum contagiosum by curettage and husking. The method consists in mechanical scraping of the nodule with a sharp Volkmann spoon or removal of formations with thin tweezers. The procedure is extremely painful and unpleasant, moreover, the removal of formations may be accompanied by bleeding. After mechanical removal of nodules, all former places their localization is treated with 5% iodine solution or other antiseptics.
These methods are not suitable for the removal of nodules for cosmetic reasons, since as a result of scraping or husking at the site of formations, sinking scars can form.
Molluscum contagiosum ointment - removal of nodules with chemicals. To remove molluscum contagiosum nodules, they can be regularly, 1 to 2 times a day, lubricated with ointments and solutions containing the following substances:
The duration of the use of any of the above drugs is determined by the rate of disappearance of molluscum contagiosum nodules. In general, as the observations of dermatologists show, for the complete removal of nodules by any of the indicated means, it is necessary to apply it continuously for 3 to 12 weeks. All of the above remedies have comparable effectiveness, so you can choose any drug that, for some subjective reasons, you like more than others. However, dermatologists recommend trying Oxolinic Ointment, Fluorouracil Ointment, or benzoyl peroxide products first, as they are the safest.
Molluscum contagiosum: removal of papules by scraping, laser, Surgitron, liquid nitrogen (advice from a dermatologist) - video
Molluscum contagiosum, treatment with antiviral drugs and immunomodulators: Acyclovir, Isoprinosine, Viferon, Allomedin, Betadine, Oxolinic ointment, iodine - video
Treatment of molluscum contagiosum in children
Treatment of molluscum contagiosum in children is carried out by the same methods as in adults, and in compliance with the general principles of therapy. That is, the optimal treatment of molluscum contagiosum in children is the absence of treatment and just waiting for the body to suppress the activity of the virus itself, and all the nodules simply disappear without a trace. But if the child scratches the nodules, or they cause him discomfort, then it is recommended to try to remove them at home with various ointments and solutions containing components to eliminate warts (for example, salicylic acid, tretinoin, cantharidin or benzoyl peroxide). These solutions are applied pointwise to the molluscum contagiosum nodules 1 to 2 times a day until they disappear.
Parents report the effectiveness of Oxolinic Ointment for removing molluscum nodules in children, so this recommendation can also be used. So, parents recommend applying a thick layer of ointment to the nodules 1 to 2 times a day until they completely disappear. At the same time, at first, the nodules under the action of the ointment may turn red and inflame, but this should not be feared, because after 1 to 2 days the formations will become covered with a crust and begin to dry out.
If it is decided to remove the nodules from the child by any surgical method, then this should be done only with the use of adequate anesthesia. The best anesthetizes the skin and, accordingly, is optimally suited for use as an anesthetic in the surgical removal of nodules of molluscum contagiosum EMLA cream 5% manufactured by AstraZeneka, Sweden. For adequate anesthesia, the cream is applied to the skin in the area of localization of nodules, covered with an occlusive film that comes with the drug, and left for 50-60 minutes. After an hour, the film is removed, the remnants of the cream are removed with a sterile cotton swab, and only after that the operation is performed to remove the molluscum contagiosum nodules.
When using EMLA cream, good level anesthesia, as a result of which the child does not feel pain and, accordingly, does not receive additional stress.
Molluscum contagiosum: causes, treatment, diagnosis and prevention. Removal of itching, inflammation and redness - video
Treatment at home
In the best way for the treatment of molluscum contagiosum at home, either pharmacy preparations or various folk remedies are suitable. made independently from medicinal herbs, which are superimposed on the nodules and contribute to their disappearance.
So, the most effective among folk methods for the treatment of molluscum contagiosum at home are the following:
Molluscum contagiosum - treatment with folk remedies: iodine, celandine, fukortsin, tar, calendula tincture - video
Before use, you should consult with a specialist.
The first thing to mention when discussing class gastropods, so this is their diversity. Almost a hundred thousand different kinds. There are so many of them that these invertebrates live in salty sea waters, having chosen both solid depths and shallow waters, and in fresh rivers, and even on the ground, and they can be found not only in green thickets, but also in deserts and rocks.
Boast gastropods can also be a variety of sizes. Some individuals do not grow more than 2 millimeters. Others are able to reach up to half a meter. They do not live long: from a couple of months to three years.
These creatures are madly in love with a humid environment, and the air must also be humidified. If they suddenly get too hot or dry, gostropods spew a lot of mucus, so their shell and its contents become protected from drying out. After that, the snails are attached to the vegetation and remain in this state until they again fall into suitable conditions. The favorite places of these creatures are dense grass thickets.
If we consider a typical representative of the class, then this is a snail that has: a body (wider in front and tapering towards the opposite end, a hump-shaped growth on the upper part), a head (a pair of tentacles and eyes on it) and a leg (dense, ends with an extension, foot-like).
All this is covered by a shell. Its shape is variable: from twisted to cone-shaped, and even a flat bowl, but always solid, without flaps. But there are individuals in which this element is not developed, i.e. completely absent, we are talking about slugs. And for example, in marine life, this part has much more modest dimensions.
If the animal is not in danger, it puts only the body in its shell. If the snail has sensed danger, the shell becomes its refuge, capable of accommodating the owner entirely. Another difference from other molluscs is the loss of bilateral symmetry.
Those. if some animals have a pair of kidneys, a pair of gills, etc., then structure of gastropods does not imply this, their organs are quite capable of functioning without a “partner”. All this is the result of the presence of a spiral shell. Invertebrates do not have hearing and voice; they are guided by touch and smell.
Structure
Let's start with the head. It can be called pronounced for mollusks. In addition, there are tentacles on this part of the body, there may be a pair, or two pairs, they have the ability to retract. The eyes sit either on the head itself or on the ends of the "horns". If it is a predator, then the mouth is placed, as a rule, on an elongated proboscis. If necessary, it unwinds outward.
The body of the mollusk is an elongated pouch, on the upper part of which rises a growth twisted in a spiral. The leg is also a part of the body, the animal uses it for movement. Wave-like movements of the sole cause the individual to move. In order to make this process easier, a special is allocated. slime. Keeping balance helps the features of the structure of the legs.
When it was possible to get food, it enters the stomach and intestines. These mollusks are able to break down food with the help of liver enzymes. After the intestine, already processed food exits through the anus, which, as a rule, exits to the right side. The kidneys perform the function of the excretory system. There can be two of them (if we are talking about the simplest organisms), or one.
A mantle is located above the body of the gastropods. In the cavity between it and the body of the individual are certain organs. Animals that live underwater have gills. Some of them have two, but mostly invertebrates are equipped with one gill (they can be located either in front of the body or in the back).
When such an animal is frightened and drawn into the shell, its mouth is closed with a small lid. If in front of you is a terrestrial creature, or periodically changing its habitat, then the respiratory gastropod system represented by one lung. In this case, when the mollusk hides in the shell, its mouth remains open.
There are also those who live on land, while storing water in the mantle cavity, and using gills for breathing. Such individuals perceive smells and tastes with the help of tentacles. Simpler and smaller varieties have no gills at all. They breathe through their skin. The heart beats next to the lung. There are no blood vessels, the blood circulates freely throughout the body. She is colorless.
From the glands with which the mantle is strewn, a substance is released due to which the shell of animals grows. Her curl can be twisted both to the right and to the left. They cannot reset this “accessory”. It is attached to the body with very strong muscles that allow the mollusk to be drawn in if something happens.
The top of the shell is its oldest part. It consists of lime salts. The shell grows most actively in warm time year, in winter, active growth slows down. This is due to the fact that the animal does not eat as densely in cold weather, and it does not have enough substances in the body to ensure the increase in the size of its "home".
Annual lines are visible on its surface; they can be used to recognize the age of the mollusk. Sometimes the shell turns into a real underwater flower bed, if the individual does not lead a very mobile lifestyle, it simply becomes overgrown with algae.
In principle, this is beneficial to the invertebrate, because plants contribute to the flow of more oxygen into its body. If the snail has chosen the bare bottom of the reservoir as a refuge, the shell may become overgrown with silt. There are also naked individuals, i.e. those who do not have a "house". These are most often those who have learned to swim in the process of evolution, for example, pteropods, or those who burrow into the ground.
Note that nervous system of gastropods, like the rest of the structure, is in close dependence on torsion. This is the name of a feature of gastropods, which implies that the shell is twisted in the opposite direction, like the body of a mollusk. The nerve ganglions of gostropods are concentrated in the anterior region of the body. And sensitivity is developed over the entire surface of the skin.
And now about reproduction, in invertebrates it occurs only sexually. These creatures reach sexual maturity on average by six months. Among the snails there are hermaphrodites (more often land-based, or living in fresh water) and dioecious (more common in the seas). If we are talking about the former, then, according to the observations of many scientists, during mating, fertilization of both individuals occurs.
After the male's germ cells enter the female's genital opening, new life may not occur immediately. The female is able to delay the process of fertilization, keeping the sperm inside herself.
When this does happen, the invertebrate lays eggs, from which already formed tiny snails, or larvae, are born. However, many publications say that among these animals there are also viviparous. To be precise, the snail does not lay eggs and leaves them inside the body until the cubs hatch from them.
Nutrition
So they call something like a tongue, which is strewn with small chitinous teeth. When this device comes into contact with plants and rubs against them, the sharp protrusions scrape off the top layer from the greenery. The same thing happens when a snail slides over sunken stones, only then it scrapes off various kinds of microorganisms that have stuck to the cobblestones.
Predators have a specific structure of the radula (grater): some of the cloves peep out of the mouth, they are able, like spikes, to stick into the body of the victim, after which they inject poison. A similar scheme works, for example, when their brethren, bivalves, become food for gastropods.
First, the predator makes a hole in their valves, for this he uses saliva, but not ordinary, but with sulfuric acid. Herbivores simply bite on algae and rotting vegetation. This, by the way, is an important role of gastropods in the ecosystem.
Kinds
If we consider types of gastropods, it is worth noting that they are divided into three subclasses:
- Anteriobranchial
The most numerous group, with a well-developed, usually spiral shell. But their main distinguishing feature is the gills lying in front of the heart. They have an amazing ability to spew pheromones, thereby attracting individuals of the opposite sex. They eat mainly bivalves, do not disdain echinoderms and coelenterates. Next, we will talk about some representatives of the subclass:
- Abalone
They called the mollusk so for specific form, its shell is very similar to a real human ear. Medium-sized invertebrate, its "house" grows up to two tens of centimeters. And from the inside it is covered with an iridescent layer of mother-of-pearl.
This feature has turned the sea creature into a craft item, because it makes popular souvenirs. Infrequently, but still, very rare and beautiful pearls are found in multicellular shells, they have an iridescent color, with green and purple tints.
In addition, the ear is actively eaten, like all delicacies, it costs a lot of money. All this leads to a decrease in the population. In some countries, for example, in New Zealand, they have already introduced a limit on the catch of molluscs. This family includes as many as seven dozen various forms individuals.
Prefers warm sea water, and lives there. Desalination of water means certain death for the ear. A solid substrate, for example, stones, is chosen as a permanent place of residence. In order to sit in the right place, they use their powerful leg.
Moreover, such a mount is so strong that the miners of delicacies have to use a knife to tear the mollusk from the base. The gills of an invertebrate are located in the mantle cavity.
The water that enters there supplies oxygen, and then exits through the holes with which the edge of the shell is strewn. Activated at dusk and at nightfall. Fertilization in them occurs outside the body of the individual, i.e. female and male sex cells are found in the water column.
- Trumpeter
It has a helical and slightly elongated shell. We often meet such people on the coast. The ideal place for their life is the cool sea. They settle at the bottom, but not at extreme depths, and move slowly as needed. If he is just walking, he overcomes only 10 sentiments of the way in a minute, but if he is looking for food, he can double his speed.
15 centimeters - this is the average height of the "house" of the snail. Inside it is perfectly smooth, without any notches. Previously, people made horns from it, now souvenirs. The mollusk is also valued by man for the taste of its meat. It also has no calories. Most trumpeters are eaten in Asia.
However, if we are talking about a giant trumpeter, then this mollusk is considered the largest among marine life. What can I say if his weight reaches 20 kilograms. An invertebrate has not two gills, but one. She extracts oxygen from a filtered special. water siphon. The same organ is for touch.
Trumpeters are eaten by starfish, crabs and even walruses. The snails themselves feast on carrion and rot. But in which case it can also manifest itself as a predator, eating worms and even small fish. Also among his favorites are bivalves.
For example, with the meat of a whole mussel, this snail cracks down in a couple of hours. A very long proboscis, which ends in a mouth, reaches inaccessible places, and even helps to scrape food from its own shell. Radula. If necessary, protrudes from the throat and grinds food before it enters the goth.
These individuals are dioecious. In the first days of summer, the breeding season is considered open. After mating, the snails lay eggs, which are sealed in a special. capsule. These pouches are attached to something solid, such as corals. If initially there are about a hundred eggs, then over time there will be no more than six of them. To get into open water. A small snail needs to gnaw through the walls of the capsule.
- Rapany
Once they could be found only in the Sea of Japan, but now these snails are widespread everywhere, especially in the Black Sea. Rapans are active predators. Their diet is bivalve brethren. They can lead a sedentary lifestyle, or slowly move along the bottom. They usually hibernate buried in the sand.
Their shell is very specific, as it is covered with several cone-shaped protrusions that look like spikes. Most often it is beige with brown stripes, and the inside is a bright carrot color. This makes it more attractive to a person, because the shell goes, usually for souvenirs.
- Triton horn (charonia)
A large gastropod, the height of the cone-shaped shell of which reaches as much as 50 cm. On the back side it has a sharp narrowed end, on the front side there is a wide almond-shaped mouth, in front of which there is the largest and convex curl. The yellowish shell is covered with brown spots.
You can meet the mollusk in tropical seas. Deep water is not for him, but the reefs are a favorite place. Unlike its counterparts, which become the prey of starfish, this predator eats them itself. And this is its great value for the biosphere. After all, the stars simply destroy the most beautiful Coral reefs, eating everything in its path.
- Marisa
It looks like a classic snail with a beige spiral shell with darker veins. They live in fresh and warm water bodies. The dimensions are not large - the shells are about 5 cm in height, but the “horns” are most often even longer. The second pair of shorter tentacles is located below, next to the eyes. The body of an invertebrate is also light, white, or yellowish.
Snails are extremely picky about food: algae, rot, alien caviar and carrion are fed. You can distinguish a female invertebrate from a male by the color of the legs. For "girls" it is dark brown, and for "boys" it is light beige.
In order to lay eggs, the mollusk finds a suitable leaf of some plant, and places the eggs under it. From eggs, not larvae, but small mollusks are born. The older, the more vertically flattened it becomes gastropod shell.
- Viviparous (lawn)
These freshwater animals need cold water and silt at the bottom of a reservoir, whether it be a lake or a river. The shell in the form of a cone twisted to the right has 5-6 curls, a lid and a chocolate color. Invertebrates live up to 6 years.
The female bears three dozen cubs in herself at once, not caviar comes out of her body, but already full-fledged snails. They still have a transparent shell and special. protective shell that disappears over time.
- Murex
The intricate shells of these mollusks have not only pimples, spikes and protrusions, but also an interesting color, often ashy white with pinkish lines. 30 centimeters - this is the approximate size of the shell of the largest representatives of the genus. These invertebrates live in the seas around the globe.
And if now they are mined solely for the purpose of decorating residential premises, but in the old days these snails were destroyed by the millions with one sole purpose - to get purple. To get at least a gram of this dye, you need to ruin thousands of mollusks. They used paint to make clothes for the nobility, paint pictures and as ink.
- tilomelania
This bright yellow snail has an almost black, elongated spiral shell. It is small - about 10 centimeters, while the shell can have up to 10 curls. This inhabitant of the lakes is a scavenger.
Belongs to the type of viviparous. A couple of babies are born, up to 1 centimeter in size. If they are gastropods in nature, then lives up to 5 years, but if you put it in an aquarium, life expectancy can increase by 2 times.
- Pulmonary
These creatures flooded fresh waters, but are most often found on land. Their shells can be of the classical form of a spiral, and in the form of a flat plate, and even completely absent. On the leg of these snails there is a special gland, from which mucus is secreted in large volumes. The latter is necessary for them to glide smoothly in the process of movement. If the mollusk lives on land, it usually has two pairs of tentacles on its head. If the animal lives in fresh waters- one pair.
Their main distinguishing feature is that the free edge of the mantle fuses with the body of the individual on the front side. The mantle cavity, in which there are no gills, but a lung is located (with the help of it the animal breathes), is associated with environment with the help of a small remaining hole. Through this passage, oxygen enters the lung. This means that aquatic inhabitants have to periodically emerge in order to take in air.
All lung molluscs are hermaphrodites.
- Achatinids
Achatina giant is the largest land snail. Its weight reaches a quarter of a kilogram, and the length of the shell grows in some cases up to 30 centimeters. The eyes of the animal sit at the ends of the first pair of tentacles. The mollusk eats everything vegetable - this is both grass and various fruits.
To produce offspring, this snail does not need a partner. She has both male and female sex cells. True, self-fertilization most often occurs if there are few other individuals around. If invertebrates come into contact, then eggs are often born in both individuals. But a lot depends on the size of the mollusks. Such a scheme only works for those who are of the same size.
If the individuals are of different sizes, then the mother is more likely to be the one that is larger. Spermatozoa can live in the animal's body for up to 2 years, and gradually fertilize the eggs. Every year the creeping creature spawns up to 6 times. At one time, this is about a hundred eggs. These white balls are placed in a pre-prepared hole. Mollusks can become sexually mature as early as six months.
This species of snail is popular as a pet.
- Prudoviki
If you look at it from above. Then you can see that on one side the shell, which is a twisted cone, is round, and on the other it is thin and sharp. Non-salty water bodies are their favorite homes. At the same time, the pond snail does not like currents, he needs stagnant water. Their age is short - only 9 months, although in captivity they can live up to two years.
Small triangular tentacles are visible on the large head. bright color they cannot boast, these are most often marsh and brown shades.
The diet contains plant foods, but they will not refuse, or fish eggs. In 60 seconds, such a snail moves 20 centimeters. Most often, she does not sit still, but is busy with something. And they also have the ability, rare for such mollusks, to swim. To do this, the pond snail turns upside down and bends it.
During the day, the pond snail floats to the surface of the reservoir at least 6 times, all in order to take air into the lung. If suddenly the pond snail is on land, or its pond is covered with a crust of ice, it can perfectly wait for the right conditions by sealing its shell with a special film. Aquarists don't like them very much. types of gastropods, all because of gluttony and fertility.
- Posterior branchial
They have a long flattened body. The leg of these individuals can grow peculiar fins (their shape resembles sunflower petals), which help the animal to move not along the bottom, but to swim freely. The posterior gills inhabit mainly the seas. The mantle organs are located on the back side of the body, respectively, and the gills of mollusks are in the same place. The shell can either overgrow and be completely covered with a mantle, or simply be reduced. These are the most unusual-looking gastropods.
- Glaucus
It looks more like an exotic fish, it is also called the "blue dragon". A long body, on the sides of which there are several processes similar to fins. By the way, body gastropod has a bright blue, very beautiful color. But this inhabitant of the water does not have a shell. It does not crawl along the bottom, but floats near the surface of the water, taking in air. The animal is small: from a couple of centimeters to five.
Glaucus is very poisonous, it is dangerous not only for those who want to eat it, but also for its victims. It feeds on other types of molluscs. Although this slug is a hermaphrodite, it cannot fertilize itself. By the way, for a person this unusual creature does not pose any danger.
- Sea hare (aplysia)
This exotic animal does not have a shell, but there is a dense beige (sometimes purple, brown, circled, or speckled) little body, along the back of which a kind of scallop runs.
Slug horns are very interestingly twisted, resembling rabbit ears. From below, the hare has two blades, thanks to this device, it can easily swim for considerable distances. In his diet only bryozoans. Settles in rocky areas. In case the mollusk is afraid of something, it spews purple ink.
- sea slug
To get nutrients. This slug does not need food, it is capable of photosynthesis. For this, he needs to say thanks to the special algae that he eats, after which he “steals” their abilities. In appearance, the slug resembles a green leaf of a tree, which, moreover, has a snail's head.
Meaning
Without gastropods, there will be a real mess in the reservoirs. notice, that the meaning of gastropods great. Not only do they eat up rotten plants, they also prevent the overgrowth of lakes, rivers, swamps and seas. Land snails are able to enrich the soil with minerals. But some types of molluscs, on the contrary, are harmful. For example, slugs destroy crops.
In addition, these creatures take their place in the food chain; some species of fish and whales cannot live without them. Do not mind eating them and a man. In addition, good crafts and decorations are obtained from shells.
