The most common types of worms in humans.

Various types of worms are found everywhere, and children account for 80% of those affected.Helminths or worms (from the Greek parasitic worm) are lower worms that parasitize the body of humans and animals.They cause pathologies called helminthiasis.According to the WHO, each year 50% of the population is infected with: pinworms (1.2 billion people), hookworms (900 million) and whipworms (up to 700 million).

What types of worms are there?To date, more than 400 species of worms found in humans have been identified.All types of human worms are divided into 2 large groups: flat and round (nematodes).In turn, the flat ones are divided into tapeworms (cestodes) and trematodes (trematodes).Cestodes are also divided into tapeworms and tapeworms.

The opinion that human worms live only in the intestines is a mistake;They can migrate with the bloodstream throughout the body and settle in a variety of places.All types of parasitic worms feed at the expense of their host and use it throughout their life cycle.

Circulation of worms in nature.

To preserve their species, parasites must constantly move to the external environment, abandon their host and settle in the body of animals, using them as intermediate hosts.In this process, carriers are of great importance: mechanical - these can be insects that carry worms over distances on their legs.Worms do not live in the body of insects.

A specific carrier or an intermediate host: in it the parasites go through only one of their development cycles.When circulating, the method of transmission of worms matters:

• contact: penetration through intact skin and mucous membranes (hookworm);
• nutritional.

Peculiarities of worm reproduction

For the most part, lower worms are hermaphrodites, but there are also worms with gender differences - nematodes.If helminths change several hosts during their development cycle (sometimes up to 4), they are called biohelminths.If they live with only one owner, they are geohelminths.

Worm development stages:

1. Egg stages: The female lays immature eggs, which mature in the external environment and then return to humans orally.
2. The second stage is when a larva hatches from the egg.This process occurs in the gastrointestinal tract.It migrates throughout the body, searching for an ideal habitat.Once found, it continues to develop into an adult.
3. The third stage is that of the adult, which again lays eggs.It should be noted that worms do not develop in all organisms, but only in those that are suitable for them, that is, for example, larvae, the host of which is an ungulate, will survive if they enter the body of a predator, but will not lay eggs there.

Types of helminthiasis

The types of helminths in humans are divided according to their habitat: luminal and tissue.In the first case, parasites live in the lumen of hollow organs, most often the intestines: ascariasis, trichuriasis, strongyloidiasis, taeniarynchiasis and others.Tissues live in the thickness of various organs and tissues.What organs can be affected by worms?They can settle and affect the hepatobiliary system, brain, eyes, lymph nodes, lungs, so the diseases can have several names:

• with liver damage - echinococcosis;
• brain damage - cysticercosis;
• lymph nodes - filariasis;
• pulmonary helminthiasis - paragonimiasis;
• Tissue helminthiasis: named after the worms: trichinosis, schistosomiasis, filariasis, toxocariasis.
• Ophthalmic helminth infections: When parasites affect the eyes and the larvae and developing stages of the worms cause more pronounced pathological changes.

Habitat

Parasitic worms are found from the Arctic to the equator, but worms that are characteristic of the tropics will not be diagnosed in residents of northern latitudes.The degree of infection of the population by helminths depends on the economic level of the country and the climate.The most common types of worms are pinworms, roundworms, and whipworms.The source of infection is the organism, the final host.

Ways of infection with worms:

1. The nutritional route consists of eating dirty or fly-infested foods, insufficient heat treatment of meat, eating raw fish, drinking unboiled water, swallowing water when swimming in reservoirs, and using the same knife for raw and cooked foods.
2. Fecal-oral transmission: contaminated household items, unwashed hands after going to the bathroom, contact with animals.
3. Transmission route.Transmission through insect bites.

pet infection

By coming into contact with a dog, you can become infected with tapeworm, echinococcus, roundworm, and pork tapeworm.Worm eggs can be in dogs' fur and, in addition, these animals have the habit of eating other people's feces while walking.From cats: the same as in dogs, as well as fluke from cats, from chickens, intestinal worms, from humans, pinworms, dwarf and porcine tapeworms, hookworms.

How do worms act in the body?

Parasites sensitize the body with their waste products, toxins and enzymes, resulting in:

• allergies and poisonings;
• mechanical damage to mucous membranes with suction cups and hooks;
• Large worms can block the intestinal lumen.
• In addition, worms eat a significant part of the incoming BZHU, which causes anemia, deficiency of vitamins, microelements, hypoxia and malnutrition;
• Digestive disorders are noted, children have a delay in psychophysical development.
• In many helminthiasis, chronic microblood loss occurs.
• Helminths worsen the course of existing pathologies, inhibit the immune system, increase the risk of tuberculosis and cancer, and reduce the effectiveness of vaccines.

Characteristics of the most common worms

What do intestinal worms look like?When cut, they are round in shape, hence their name.Roundworms have their own characteristics.First of all, their extraordinary resistance: they remain alive in formaldehyde for 5 years.In addition, they are distinguished by a simple development cycle, a straight tube-shaped digestive system and rapid reproduction.

Pinworms cause enterobiasis (anthroponotic disease, dirty hands disease).They look like small white worms up to 1 cm (males are only 3 mm), the end of the body is slightly pointed.They live in the lower parts of the small intestine and in the initial part of the large intestine.They are contact worms.Egg laying occurs in the anus area.The development cycle lasts 2 weeks, they live 1 to 2 months.More common in children.They are attached to the intestinal wall by vesicles in the head.Female pinworms descend to the anus at night and lay eggs here.At the same time, they secrete a special type of fluid that causes itching.A child scratches his butt and self-infection occurs.After laying eggs, the females die.The damage they cause is the release of enzymes that irritate the intestinal walls and contribute to their inflammation.

Nematodes cause ascariasis.These are reddish-white nematodes up to 50 cm long and up to 6 cm wide.Males have a curved end.Nematodes live in the small intestine, but the larvae actively migrate throughout the body and their life cycle reaches up to a year.Worm larvae live in the lungs.Its waste products cause poisoning and intestinal obstruction.

Parasites are geohelminths, that is, they develop in the soil and from there reach humans.They are distinguished by their enormous fertility, up to 240 thousand eggs per day.The eggs have a very strong three-layer shell and fall easily to the ground.Here, under the influence of oxygen, humidity and a certain temperature, larvae form in them.This process can take from 2 weeks to several months, depending on the temperature.Such a mature egg with a larva again enters the person orally.The larva emerges in the intestines and is transported throughout the body through the bloodstream.Its favorite habitat is the alveoli of the lungs, since it has access to oxygen there and the larva is aerobic.Adults are anaerobes.Having reached 3-4 mm in length, after 4-5 days the larva enters the bronchi, which causes cough.When coughed, it is swallowed and returns to the intestines, where it develops to maturity.The life cycle of the parasite reaches up to one year.

Whipworms cause trichuriasis, belong to the nematodes, have a color that ranges from grayish to reddish, reach 2 to 5 cm and have a sharp tip similar to a hair, hence their name.The parasite attaches to the intestinal wall and feeds on the blood and mucosal tissues of the host.It lives in the large intestine and appendix, here the larvae reach sexual maturity and lay 3.5 thousand eggs daily.The life cycle of the parasite is 4 to 5 years.By damaging the intestinal wall, they contribute to its damage: causing appendicitis, diarrhea, abdominal pain, anemia.Helminth eggs enter the soil with human feces, where they can persist for up to 2 years.

Toxocara causes toxocariasis.This is a yellowish worm that looks like an intestinal worm, but is between 15 and 20 cm long.It is a biohelminth;humans become infected through dogs.They live in the form of eggs.In the human intestine, larvae emerge from them.They migrate throughout the body, damaging internal organs and causing allergies.The severity of the clinic depends on the immunity and the number of helminths.Laying eggs per day - up to 250 thousand.Life cycle: up to 10 years.

Trichinella spiralis causes trichinosis, which is considered the most dangerous of the helminthiasis, often resulting in death.The nematode is only 5 mm long.Infestation occurs by eating undercooked pork.Trichinella in the intestine is fertilized, the larvae gestate and hatch inside the female.At one end, the female adheres to the intestinal wall and expels up to 2,000 live larvae.This process is called ovoviviparity and lasts 3 to 4 days.The larvae are carried by the bloodstream and settle in the striated muscles, especially in the masticatory, oculomotor, respiratory and shoulder flexor tracts.The disease is serious: 2 weeks after the invasion, pain appears in the abdomen, muscles, head and joints, fever, swelling of the face and intoxication.In the muscles, after a month, the larvae become encapsulated in a spiral shape and can remain in the cyst state for 20 years without losing their viability.After 1.5 months, recovery occurs with appropriate treatment.

Hookworm and necator are similar to each other, so their helminthiasis receives a common name - hookworm.They are up to 1.5 cm long and parasitize the duodenum.Helminth is common, but rarely detected.The larvae can penetrate the skin upon contact with soil.The development cycle is very similar to that of intestinal worms.Hookworm lives in the intestines and feeds only on blood.An individual can absorb 0.35 ml of blood per day.Therefore, a characteristic feature is anemia and dysproteinemia.

Flatworms have a flattened shape.They have no gender differences;They are hermaphrodites.They are attached to the intestines using hooks and suction cups.

Bull tapeworm is a tapeworm that causes tanehyrinchiosis.It has a small head with 4 suction cups and 6 hooks and a ribbon body of 1000 segments, which reaches 20 m in length.The parasite is a biohelminth, the infection occurs through beef, where its larvae are found.Each segment contains hundreds of thousands of eggs.Without treatment, the tapeworm parasitizes humans for up to 20 years.It lives in the small intestine, sucking nutrients from all over the surface of the body.Lives up to 10 years.

The pork tapeworm is a tapeworm that causes taeniasis or cysticercosis.It reaches 3-8 m and has a double edge of hooks.The life cycle is 20 to 30 years.It can live in any organ and is found in undercooked pork.The cycle is similar to the bullish tapeworm.The segments of this tapeworm can emerge from the anus, here, on the surface of the skin, they burst and the eggs come out.The helminth parasitizes the intestines, causing allergies and gastrointestinal problems.

Broad tapeworm causes diphyllobothriasis.The parasite is more than 10 m long, flat and wide.Biohelminths reach humans through freshwater fish or crustaceans.For dozens of years, the worms parasitize in the small intestine and cling to its wall.In 25 days, the parasites become adults.They feed on blood, causing diarrhea and abdominal pain.

Echinococcus is a biohelminth, a small tapeworm, up to 3-5 mm.On its head there are 2 corollas of hooks and suction cups;the parasite has 4-5 segments.The last is your reproductive system.In the organs it forms cysts up to 10 cm (Finnish), where the eggs and larvae are located.The cysts destroy the surrounding tissue.They may rupture and then develop toxic shock or multiple new cysts.The final owner is the wolf, the intermediate owner is the man.Infection due to nutrition or after contact with domestic animals.In the intestine, larvae (oncospheres) emerge from the eggs and are transported throughout the body through the bloodstream.As a rule, they settle in the parenchyma of the liver and lungs, but they also live in the intestines.Cysts can only be removed surgically.

The cat fluke is a liver fluke, cat fluke or Siberian fluke.Causes opisthorchiasis.It has a lanceolate shape, 1-2 cm long and 2 mm wide, with 2 oral suckers on the head.People become infected through infected freshwater fish that have eaten a snail or crustacean with worm eggs.Humans are the main host.The parasite lives in the lumen of the small intestine and in the bile ducts.The life cycle is up to 20 years;Thousands of individuals parasitize an organism at a time.The acute phase of the disease is characterized by pain in the upper abdomen, fever, nausea, myalgia, diarrhea and skin rashes.When the process becomes chronic, symptoms of hepatocholecystitis are noted that do not disappear even after the worms are expelled.

Course of the disease and symptoms.

During the acute phase, symptoms can appear at different times, depending on the incubation period, but most often begin after 2 to 3 weeks.The most common symptoms: allergic rash, lymphadenopathy, development of local or general edema, arthralgia and myalgia.When it migrates to the lungs, there may be coughing, choking attacks, stool disturbances (diarrhea), nausea and vomiting.

In the chronic phase, the symptoms depend on the organ where the parasites have settled and their number.Key features include:

• frequent itching in the anal area;
• headaches;
• dizziness;
• sleep disorders;
• flatulence;
• rash and itching;
• exhaustion with increased appetite;
• joint and muscle pain;
• yellowish color of the skin;
• fatigue.
• prolonged low fever may occur;
• discomfort in the umbilical region or in the right hypochondrium;
• periodic nausea and vomiting;
• bruxism;
• apathy.

The patient presents with pale, dry skin, loss of hair, eyebrows, eyelashes, brittle nails, cavities, bleeding gums, and bad breath.

Diagnostic and preventive measures.

To make a diagnosis, a scraping is taken from the rectum and perianal area, and a stool analysis is also performed.In this case, the worms are very clearly visible under a microscope.A blood test is performed to determine the balance of eosinophils and proteins.Sputum, stomach and duodenal contents can be examined.

Any helminth in humans is prevented by constant personal and public hygiene and sufficient heat treatment of meat and fish.Regular veterinary exams and additional treatments are necessary for all pets.