The most common types of worms in humans

All kinds of worms can be found everywhere, 80% of them are children.Worms or helminths (from Greek parasitic helminth) are lower worms that live in the bodies of humans and animals.They cause a condition called helminthiasis.According to the World Health Organization, 50% of the population is infected each year with: pinworm (1.2 billion people), hookworm (900 million people) and whipworm (up to 700 million people).

What types of worms are there?To date, more than 400 species of human worms have been identified.All types of worms in humans are divided into two main categories: flat worms and round worms (nematodes).Flatworms, in turn, are divided into tapeworms (tapeworms) and flukes (flukes).Tapeworms are further divided into tapeworms and tapeworms.

It is a misconception that human worms only live in the intestines.They can migrate throughout the body with the blood and settle in different places.All types of parasites feed on their hosts and exploit them during their life cycle.

The cycle of worms in nature

To protect their species, parasites must constantly leave their hosts and enter the external environment and colonize animals, using them as intermediate hosts.In this process, vectors are very important: Mechanical vectors – These vectors can be insects that carry the worms over long distances on their legs.Worms do not live inside insects.

A specific vector or intermediate host - in which the parasite undergoes only one developmental cycle.When spreading, how a worm spreads is important:

• Contact - Penetration of intact skin and mucous membranes (hookworms);
• Nutrition.

Characteristics of worm reproduction

Most lower worms are hermaphrodites, but there are some worms with sexual differences - nematodes.If worms change multiple hosts (sometimes up to 4) during their developmental cycle, they are called biological worms.If they live with only one owner, they are soil worms.

Developmental stages of worms:

1. Egg stage – The female lays immature eggs, which mature in the external environment and are then returned to humans orally.
2. The second stage is when the larvae hatch from the eggs.This process occurs in the gastrointestinal tract.It migrates throughout its body in search of an ideal habitat.After finding it, it continues to develop into an adult.
3. The third stage is the adult worm, which lays eggs again.It should be noted that worms do not develop in all organisms, but only in those that are suitable for themselves, that is, for example, larvae, whose hosts are ungulates, if they enter the body of a predator, they will survive, but they will not lay eggs there.

Types of helminthiasis

Types of human worms are divided according to their habitat: luminal worms and tissue worms.In the first case, parasites live in the lumen of hollow organs, most commonly the intestines: ascariasis, whipworm, strongyloidiasis, handworm disease, etc.Tissue lives in various organs and tissue thicknesses.What organs are affected by worms?They can colonize and affect the hepatobiliary system, brain, eyes, lymph nodes, lungs, so the disease can have several names:

• For liver damage - hydatid disease;
• Brain damage - cysticercosis;
• Lymph nodes - filariasis;
• Pulmonary worm disease - paragonimiasis;
• Histohelminthiasis - by name of worms: trichinellosis, schistosomiasis, filariasis, toxocariasis.
• Ocular helminth infection - When parasites affect the eye, the more obvious pathological changes are caused by the larval and developmental stages of the worms.

habitat

Parasites are found from the Arctic to the equator, but those endemic to the tropics will not be diagnosed in residents of northern latitudes.The extent of helminth infection in a population depends on the country's economic level and climate.The most common types of worms are pinworms, roundworms, and whipworms.The source of infection becomes the organism—the ultimate host.

Worm infection route:

1. Nutritional pathways include eating unwashed food or food with flies in it, insufficient heat treatment of meat, eating raw fish, drinking raw water, swallowing water while swimming in the reservoir, and eating raw and cooked food with the same knife.
2. Fecal-oral transmission: contaminated household items, failure to wash hands after using the toilet, contact with animals.
3. transmission path.Transmitted through insect bites.

pet infection

You can become infected with tapeworms, Echinococcus, roundworms, and solium tapeworms through contact with dogs.The eggs can be on a dog's fur, and in addition, these animals have a habit of eating other people's feces while walking.From cats: the same as in dogs, as well as cat flukes, from chickens - roundworms, from humans - pinworms, dwarf and pork tapeworms, hookworms.

How do worms affect the body?

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

• allergies and poisoning;
• Suction cups and hooks cause mechanical damage to mucous membranes;
• Large worms can clog the intestinal lumen.
• In addition, worms eat a large part of the incoming BZHU, leading to anemia, vitamin and trace element deficiencies, hypoxia, malnutrition;
• Digestive system diseases were noted, and the psychophysical development of children was delayed.
• Chronic microblood loss occurs with many helminthiasis.
• Helmins can worsen existing pathological processes, 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?When cut, they take on a round shape, which is how they get their name.Roundworms have their own characteristics.First, there's their extraordinary endurance: they can survive in formaldehyde for 5 years.In addition, they are characterized by a simple development cycle, a straight tube-shaped digestive system, and a fast reproduction rate.

Pinworms cause enterobiasis (man-made disease, dirty hand disease).They look like small white bugs, up to 1 centimeter long (males only 3 millimeters), with a slightly pointed end.They live in the lower part of the small intestine and the beginning of the large intestine.They are contact worms.Egg laying occurs in the anal area.The development cycle lasts 2 weeks and their lifespan is 1-2 months.More common in children.They attach to the intestinal wall via head vesicles.Female pinworms descend to the anus at night and lay eggs here.At the same time, they secrete a special fluid that causes itching.Self-infection occurs when a child scratches his butt.After laying eggs, the female dies.The harm they cause is that they release enzymes that irritate the intestinal wall and cause inflammation.

Roundworms cause ascariasis.These are red and white roundworms that can be up to 50cm long and 6cm wide.Males have a curved end.Roundworms live in the small intestine, but the larvae actively migrate throughout the body and have a life cycle that can last up to a year.Worm larvae live in the lungs.Their waste products can cause poisoning and intestinal obstruction.

The parasites are soil worms, that is, they grow in the soil and from there reach humans.They are known for their enormous fecundity, laying up to 240,000 eggs per day.The eggs have a very strong three-layered shell and fall easily into the soil.Here, under the influence of oxygen, humidity and a certain temperature, larvae form.This process can take anywhere from two weeks to several months, depending on the temperature.Such a mature egg with larvae enters the human mouth again.The larvae emerge in the intestines and are transported throughout the body via the bloodstream.Its favorite habitat is the alveoli because oxygen is available there and the larvae are aerobic.Adults are anaerobes.When the larvae reach 3-4 mm in length, they enter the bronchi 4-5 days later, causing coughing.When coughed, it is swallowed and returned to the intestine, where it matures.The life cycle of the parasite lasts up to a year.

Whipworms, which cause whipworm disease, belong to the nematode class. Their body color ranges from gray to red, they are 2-5 cm long, and they have a sharp hair-like head at the head, hence the name.The parasite attaches to the intestinal wall and feeds on the host's blood and mucosal tissue.It inhabits the large intestine and appendix, where the larvae reach sexual maturity and lay 3,500 eggs per day.The life cycle of the parasite is 4-5 years.By destroying the intestinal wall, they can cause damage: causing appendicitis, diarrhea, abdominal pain, and anemia.Worm eggs enter the soil in human feces and can survive for up to two years.

Toxocara causes toxocariasis.This is a yellowish worm, similar to roundworms, but 15-20 cm long.It is a biological worm; humans are infected by dogs.They live in the form of eggs.In the human intestine, larvae emerge from it.They migrate throughout the body, damaging internal organs and causing allergies.Clinical severity depends on immunity and the number of worms present.Up to 250,000 eggs are laid per day.Life cycle - up to 10 years.

Trichinella spiralis causes trichinellosis, which is considered the most dangerous helminth disease because it often results in death.Nematodes are only 5 mm long.Infection can occur when undercooked pork is eaten.Trichinella spiralis is fertilized in the intestines and the larvae gestate and hatch inside the female.The female attaches to the intestinal wall at one end and expels up to 2000 live larvae.This process is called ovoviviparity and takes 3-4 days.Larvae are disseminated through the bloodstream and colonize in striated muscles, especially in the muscles of mastication, oculomotor, respiratory tract, and shoulder flexors.Severe condition: 2 weeks after the attack, symptoms such as pain in the abdomen, muscles, head and joints, fever, facial swelling, and poisoning appear.In the muscles, after a month, the larvae are encased in a spiral shape and can remain in a cystic state for 20 years without losing vitality.Recovery is possible with appropriate treatment after 1.5 months.

Hookworms and hookworms are similar to each other, so their helminthiasis has been given a common name - hookworms.They are up to 1.5 cm long and live in the duodenum.Worms are common but rarely detected.Larvae can penetrate the skin after contact with soil.The development cycle is very similar to that of roundworms.Hookworms live in the intestines and feed exclusively on blood.A person can absorb 0.35 ml of blood per day.Therefore, a characteristic feature is anemia and dysalbuminemia.

Flatworms have a flat shape.They have no gender differences; they are hermaphrodites.They attach to the intestine using hooks and suction cups.

Bull tapeworm is a tapeworm that causes taeniasis.Its head is small, with 4 suction cups and 6 hooks. The belt body has 1000 segments and the length reaches 20 m.This parasite is a biological worm and infection occurs through the beef where its larvae reside.Each section contains hundreds of thousands of eggs.If left untreated, tapeworms can live in the human body for up to 20 years.It lives in the small intestine and draws nutrients from the entire surface of the body.Lifespan up to 10 years.

Pork tapeworm is a tapeworm that causes taeniasis or cysticercosis.Up to 3-8 m long, with double edge hooks.The life cycle is 20 to 30 years.It can live in any organ and is found in undercooked pork.This cycle is similar to a bullish tapeworm.Segments of this tapeworm can crawl out of the anus, rupture on the surface of the skin and lay eggs.Worms live in the intestines and cause allergies and gastrointestinal problems.

The widespread tapeworm causes dilofilariasis.The insect body is more than 10m long, flat and wide.Biological worms reach humans via freshwater fish or crustaceans.For decades, the worms live in the small intestine, clinging to its walls.After 25 days, the parasites will grow into adults.They feed on blood and cause diarrhea and abdominal pain.

Echinococcus is a biological worm, a small tapeworm measuring up to 3-5 mm.There are 2 corollas with hooks and suckers on the head; the parasite has 4-5 segments.The last one is his reproductive system.In the organ, it forms cysts (Finns) up to 10 cm long, in which the eggs and larvae are located.Cysts destroy surrounding tissue.They may rupture and then go into toxic shock or develop multiple new cysts.The ultimate master is a wolf, and the middle master is a human.Acquired through nutrition or contact with livestock.In the intestines, larvae (methyllarvae) hatch from the eggs and are transported throughout the body through the bloodstream.Typically, they colonize the parenchyma of the liver and lungs, but also live in the intestines.Cysts can only be removed surgically.

Cat flukes are liver flukes, cat flukes or Siberian flukes.Causes posterior testicular disease.It is lanceolate, 1 to 2 cm long and 2 mm wide, with 2 mouth suckers on its head.People become infected by eating infected freshwater fish from snails or crustaceans that carry the eggs.Humans are the primary host.The parasite lives in the lumen of the small intestine and bile ducts.Life cycle lasts 20 years; thousands of individuals parasitize a single organism at the same time.The acute phase of the disease is characterized by epigastric pain, fever, nausea, myalgia, diarrhea, and rash.When this process becomes chronic, symptoms of liver cholecystitis appear, which do not go away even after passing the worms.

Course and symptoms

In the acute phase, symptoms may appear at different times depending on the incubation period, but in most cases they appear after 2-3 weeks.The most common symptoms: allergic rash, lymphadenopathy, local or general edema, arthralgia and myalgia.When migrating to the lungs, coughing, choking, disturbed bowel movements (diarrhea), nausea, and vomiting may occur.

In the chronic stage, symptoms depend on the organs in which the parasites have colonized and their numbers.Key features include:

• Frequent itching in the anal area;
• Headache;
• Dizziness;
• sleep disorders;
• flatulence;
• rash and itching;
• Exhaustion due to increased appetite;
• joint and muscle pain;
• yellowing of skin;
• fatigue.
• A prolonged, low-grade fever may occur;
• Discomfort in the umbilical area or right rib;
• cyclic nausea and vomiting;
• Bruxism;
• indifferent.

Patients have pale, dry skin, loss of hair, eyebrows, and eyelashes, brittle nails, tooth decay, bleeding gums, and bad breath.

Diagnostic measures and prevention

To make a diagnosis, scrapes from the rectal and perianal area are taken, and stool analysis is performed.In this case, the worms are very clearly visible under the microscope.Blood tests for eosinophils and protein balance.Sputum, gastric, and duodenal contents may be examined.

Any parasite in humans can be prevented through continued personal and public hygiene, and adequate heat treatment of meat and fish.All pets require regular veterinary examinations and further treatment.