The most common types of worms in humans

Various types of worms are found everywhere and 80% of those affected are children.Helminths or worms (from the Greek parasitic worm) are lower worms that parasitize the body of humans and animals.They cause diseases called helminthiasis.According to the WHO, every 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 present in humans have been identified.All types of worms in humans are divided into 2 large groups: flat and round (roundworms).In turn, flat ones are divided into tapeworms (cestodes) and trematodes (flukes).Tapeworms are also divided into tapeworms and tapeworms.

The opinion that worms in humans live only in the intestine is a misconception;they can migrate with the bloodstream throughout the body and settle in a variety of locations.All types of parasitic worms feed on their host and use it for their life cycle.

Movement of worms in nature

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

A specific carrier or intermediate host: in it the parasites undergo only one of their development cycles.When circulating, the method of transmission of worms is important:

• 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.

Stages of development of worms:

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, looking for an ideal habitat.After finding it, it continues to develop until it becomes an adult.
3. The third stage is the adult, which lays eggs again.It should be noted that worms do not develop in all organisms, but only in those suitable for themselves, that is, for example, larvae, for which the host is an ungulate, will survive if they enter the body of a predator, but do not lay eggs there.

Types of helminthiasis

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 in the intestine: ascariasis, trichuriasis, strongyloidiasis, teniarinchiasis and others.Tissues live in the thickness of various organs and tissues.Which organs can be affected by worms?They can settle and affect the hepatobiliary system, brain, eyes, lymph nodes, lungs, so diseases can have different names:

• for liver damage - echinococcosis;
• brain damage - cysticercosis;
• lymph nodes - filariasis;
• pulmonary helminthiasis - paragonimiasis;
• tissue helminthiasis - by the name of worms: trichinosis, schistosomiasis, filariasis, toxocariasis.
• ophthalmic helminth infections - when parasites affect the eyes and more pronounced pathological changes are caused by the larvae and developmental stages of worms.

Habitat

Parasitic worms are found from the Arctic to the equator, but worms characteristic of the tropics will not be diagnosed in residents of northern latitudes.The degree of infection of the population with helminth infections 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 the infection becomes the organism, the final host.

Ways of infection with worms:

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

Pet infection

Through contact with a dog, you can contract tapeworm, echinococcus, roundworm, and pork tapeworm.Worm eggs can be found on the fur of dogs and these animals also have the habit of eating other people's feces while walking.From cats - the same as from dogs, as well as cat fluke, from chicken - roundworms, from humans - pinworms, dwarf and pig tapeworms, hookworms.

How do worms affect the body?

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

• allergies and intoxications;
• mechanical damage to the mucous membranes with suction cups and hooks;
• Large worms can obstruct the intestinal lumen.
• in addition, worms eat a significant part of the incoming BZHU, which causes anemia, deficiency of vitamins, microelements, hypoxia, malnutrition;
• digestive disorders are noted, children have a delay in psychophysical development.
• With many helminthiases, chronic loss of microblood occurs.
• helminths worsen the course of existing pathologies, suppress the immune system, increase the risk of tuberculosis and cancer, and reduce the effectiveness of vaccinations.

Characteristics of the most common worms

What do roundworms look like?Once cut they have a round shape, hence their name.Nematodes have their own characteristics.First of all, this is 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 long (males are only 3 mm), the end of the body is slightly pointed.They live in the lower parts of the small intestine and the beginning of the large intestine.They are contact worms.Egg laying occurs in the anus area.The development cycle lasts 2 weeks, they live 1-2 months.More common in children.They are attached to the intestinal wall by head vesicles.Female pinworms descend into the anus in the evening and lay their eggs there.At the same time they secrete a special type of liquid that causes itching.A child scratches his bottom 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.

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

The parasites are geohelminthes, that is, they develop in the soil and from there reach humans.They stand out for their enormous fertility, up to 240 thousand eggs per day.The eggs have a very resistant three-layered shell and easily fall into the ground.Here, under the influence of oxygen, humidity and a certain temperature, larvae are formed.This process can take anywhere 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 intestine and is carried throughout the body by the bloodstream.Its preferred habitat is the lung alveoli, since there is access to oxygen and the larva is aerobic.Adults are anaerobic.Having reached a length of 3-4 mm, after 4-5 days the larva moves into the bronchi, causing coughing.When coughed, it is swallowed and returns to the intestine, where it develops to maturity.The life cycle of the parasite is up to a year.

Whipworm causes trichuriasis, belongs to roundworms, has a grayish to reddish color, reaches 2-5 cm, has a sharp hair-like head end, from which it takes its name.The parasite clings to the intestinal wall and feeds on the host's blood and mucosal tissues.It lives in the large intestine and appendix, here the larvae reach sexual maturity and lay 3.5 thousand eggs per day.The life cycle of the parasite is 4-5 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.It is a yellowish worm that resembles a nematode, but is 15-20 cm long.It is a biohelminth;humans get infected from dogs.They live in the form of eggs.Larvae emerge in the human intestine.They migrate throughout the body, damaging internal organs and causing allergies.The severity of the clinic depends on immunity and the number of helminths.Egg laying per day: up to 250 thousand.Life cycle: up to 10 years.

Trichinella spiralis causes trichinosis, considered the most dangerous of helminthiases, as it often leads to death.The nematode is only 5 mm long.The infestation occurs when undercooked pork is eaten.The trichinella in the intestine is fertilized, the larvae are gestated and hatch inside the female.At one end, the female attaches to the intestinal wall and launches up to 2 thousand live larvae.This process is called ovoviviparity and takes 3-4 days.The larvae are transported through the bloodstream and settle in the striated muscles, especially in the masticatory, oculomotor, respiratory tracts and shoulder flexors.The disease is serious: 2 weeks after the invasion, pain in the abdomen, muscles, head and joints, fever, swelling of the face and intoxication appear.In the muscles, after a month, the larvae are encapsulated in a spiral shape and can remain in a cyst-like state for 20 years without losing viability.After 1.5 months, recovery occurs with adequate treatment.

Hookworm and necator are similar to each other, so their helminthiasis is given 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 when in contact with the soil.The development cycle is very similar to that of nematodes.The hookworm lives in the intestine 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 intestine by hooks and suckers.

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

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 bull tapeworm.Segments of this tapeworm can crawl out of the anus, here they burst onto the surface of the skin and the eggs come out.Helminths parasitize the intestine, causing allergies and gastrointestinal problems.

Broad tapeworm causes diphyllobothriasis.The parasite is more than 10 m long, flat and wide.The biohelminth reaches humans via freshwater fish or crustaceans.For decades, worms parasitize the small intestine, clinging 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 long.On the head there are 2 corollas of hooks and suckers;the parasite has 4-5 segments.The last one is its reproductive system.In the organs it forms cysts up to 10 cm long (Finnish), where eggs and larvae are found.Cysts destroy surrounding tissue.They can rupture, so toxic shock develops or multiple new cysts develop.The final owner is the wolf, the intermediate owner is man.Infection through feeding or after contact with pets.In the intestine, larvae (oncospheres) emerge from the eggs and are carried throughout the body by the bloodstream.They are deposited, as a rule, in the parenchyma of the liver and lungs, but also live in the intestine.Cysts can only be removed surgically.

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 primary host.The parasite lives in the lumen of the small intestine and bile ducts.The life cycle lasts up to 20 years;thousands of individuals parasitize simultaneously in an organism.The acute phase of the disease is characterized by upper abdominal pain, fever, nausea, myalgia, diarrhea, and skin rashes.When the process becomes chronic, the symptoms of hepatocholecystitis are noted and do not disappear even after the expulsion of the worms.

Course of the disease and symptoms

During the acute phase, symptoms can appear at different times, depending on the incubation period, but in most cases they begin after 2-3 weeks.The most common symptoms: allergic rash, lymphadenopathy, development of local or general edema, arthralgia and myalgia.During migration to the lungs, coughing, choking attacks, stool disorders (diarrhoea), nausea and vomiting may occur.

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;
• heachache;
• dizziness;
• sleep disorders;
• flatulence;
• skin rash and itching;
• exhaustion with increased appetite;
• joint and muscle pain;
• yellowness of the skin;
• fatigue.
• prolonged low-grade fever may occur;
• discomfort in the umbilical region or right hypochondrium;
• periodic nausea and vomiting;
• bruxism;
• apathy.

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

Diagnostic measures and prevention

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

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