Types of worms in humans and ways to infect them

Worms are representatives of the lower worms that live in the human body. The disease associated with the infection of a person with different types of worms is called helminthiasis. This disease is not uncommon and occurs in certain segments of the population. Children are susceptible to infection with pinworms, hunters - Trichinella, fishermen and lovers of Japanese cuisine (raw fish in the form of sushi) suffer from diphyllobotriasis. Many diseases, paradoxically, can occur in the human body due to helminthiasis infection. To date, the theory of the relationship between cancer and parasitic infections is one of the most current. In the presence of helminthiasis, the symptoms do not always appear, and if, however, patients with this disease experience any unpleasant and uncomfortable sensations, they are perceived as signs of other diseases. The patient has been treated for years for pancreatitis, gastritis or colitis, without suspecting that the cause of his ailments is helminthiasis.

How the infection occurs

Worms bring a lot of trouble to a person

parasites in the human body

The helminth infection proceeds as follows:

  • Through unwashed hands
  • In contact with soil
  • after insect bites
  • Because of dirty hands
  • When eating raw meat and fish
  • After eating unwashed fruits and vegetables
  • After contact with an animal
  • After contact with infected people

Mature eggs of parasites can be found in soil, water, food (raw and poorly cooked meat or fish). Rare cases of the disease occur due to insect bites. The mechanism of helminthiasis infection is oral-fecal. Man swallows the eggs of parasites with food, water. There are also contact-household methods of infection. They occur when hands have not been thoroughly washed after contact with earth or sand.

Vegetables and berries grown in the ground that are not sufficiently washed are also a source of worm infection. Children who play with the yard and pets are at risk of becoming infected with worms. Pets that roam the streets freely can bring helminth eggs into the house. Flies and other insects, after contact with animal feces sitting on food, can easily transfer helminth eggs. Surprisingly, human-to-human transmission is also possible. This is what happens: the female squirrel can crawl out of the gut and lay eggs right on the underwear, causing severe itching. A person scratching an itchy area may come into contact with other toilets and household items. These items fall into the hands of other family members and then become infected.

Infection through water is also possible. Many parasitic eggs easily end up in open water and wells. Drinking unboiled well water is extremely dangerous.

Types of helminthiasis

Helminthiasis differs in the way they enter the human body:

  1. Biohelminths
  2. Geohelminth
  3. infected

Biohelminths are transmitted to humans through contact with animals. Geohelminths can be infected through the soil. Infectious occurs when in contact with an infected person. The disease manifests itself differently depending on the mode of infection, the number of worms, the degree of their adaptation in each human organ.

Stages of helminthiasis

how worm infection occurs

The most destructive effect on the body is not produced by adults, but by their larvae. Adult individuals have already chosen a cozy place for themselves in the human body, and the larva travels through the organs and leaves behind their lesions. The most common habitat of parasites is the gastrointestinal tract. Different types of parasites prefer different habitats. Thus, roundworms are found in the small intestine, and pinworms settle in the large intestine and lower parts of the small intestine. According to the habitat of the parasites, helminthiases are:

  • translucent
  • plat

The translucent ones are located in the lumen of the genitals, and the tissues - inside the tissues. Depending on the growth, the parasites can change their habitat, moving from the translucent form to the tissue. Helminthiasis develops in two stages:

  1. sharp
  2. Chronic

The acute phase lasts from a week to a month, and the chronic phase lasts until healing. The acute phase begins with the introduction of the egg and continues until the parasite matures and grows. The disease is manifested by allergic reactions to a foreign organism. During the chronic stage of the disease, various reactions of the body occur. During this period, the parasite travels through the body in search of shelter. The disease is accompanied by disorders of organs and systems in the human body. Integrating into the immune system of the human body, parasites consume substances necessary for their growth and development. This leads to metabolic disorders, disorders of the digestive system, difficulty absorbing vitamins and minerals.

In addition to this damage, parasites throw their waste products into the human body, poisoning the body, leading to intestinal disorders, reduced immunity and the development of bacterial infections. Parasites contribute to the risk of developing cancer. This is due to the negative impact on the immune system and stimulating the process of cell division. Often the patient is examined by many specialists who find a bunch of diseases in him. And in this case, only one doctor, a parasitologist, can replace all the specialists.

Classification of helminths

roundworms in humans

roundworms are quite common

Types of worms in humans:

  1. flatworms
  2. roundworms

Flatworms include:

  • Trematodes (opisthorchiasis, schistosomes, paragonim)
  • Cestodes (tapeworm, tapeworm, echinococcus, alveococcus)
  • Roundworms or nematodes:
  • Blade
  • Ascaris
  • hookworm
  • Trichinella

Such a classification of helminths is presented in the medical literature. To successfully solve such a problem as helminthiasis, it is necessary to find an in-depth description of the structure and life cycle of parasites.


Another name for trematodes is flukes. These parasites are flat, leaf-like or lanceolate with two suckers. One suction cup is in the mouth and the other, which is used for attachment, is in the peritoneum. All representatives of the flukes enter the body through an intermediate host. These parasites are mostly hermaphrodites.


This methyl is a worm up to 1. 3 cm long with two suckers. Opisthorchiasis is a hermaphrodite, parasitizing the liver, gallbladder, pancreas in humans and some predators (foxes, dogs, cats). Eggs of opisthorchiasis leave the human or animal body with feces. When they enter the tank, these eggs are swallowed by freshwater mollusks, inside which the larvae hatch and develop. The process of development and maturation of larvae lasts two months. The larvae then crawl out of the mollusks and penetrate the skin to carp the fish. After six weeks, the larvae become full-fledged mature parasites. Opisthorchiasis enters the body of an animal or human after eating infected fish. This worm can live in a living organism for up to 20 years. Symptoms of opisthorchiasis:

  1. alergy
  2. Weakness
  3. headache
  4. Dizziness
  5. depression
  6. Loss of consciousness

Damage to the body from opisthorchiasis:

  • Poisoning with the waste products of the parasite
  • Damage to liver tissue
  • Damage to the gallbladder
  • Impaired bile flow
  • Inflammation of the pancreas
  • Secretory dysfunction
  • Decreased gastric motility
  • Thickening of the walls of some organs, resulting in the emergence of tumors.

The chronic course of the disease is characterized by:

  • Weight after eating
  • Pain
  • vomiting
  • nausea

Habitats of opisthorchiasis in fish-rich rivers:

  1. Where
  2. Dnieper
  3. The Neman Delta

Prevention of infection: To avoid infection with opisthorchiasis, do not eat raw fish. The larvae die during the heat treatment of the products. Dried fish can be eaten only if it is pre-salted. Also, larvae die when the fish is frozen for a long time.


garlic for worms

These parasites are of different sexes, look like a needle with a length of 0. 4 to 2. 6 cm. Females are longer than males and larger, producing 3, 000 eggs per day. The method of reproduction, as in previous species of parasites, is by freshwater mollusks. The larva enters the human body through the skin, mucous membranes, while swimming in a freshwater tank. It can also enter the body of a person who accidentally swallows water while swimming. One day after penetration, the larva becomes an adult and enters the peripheral veins, through which it is directed to the lungs and venous vessels. There the schistosome reaches sexual maturity.

Schistosoma lays eggs in the intestines, mucous membranes, bladder. The eggs are then excreted from the human body in urine or feces and begin the path of development again. Schistosoma has lived in the human body for decades, causing harm and infecting new individuals. Problems that occur during schistosome infection, the human body is no longer caused by adults, but by their eggs. Only half of the eggs are released from the body, the rest accumulate in the organs. The eggs of this parasite have thorns that damage a person's internal organs, and ulcers often occur in those infected. Patients with schistosomiasis experience the following symptoms:

  • Appetite disorder
  • anemia
  • Enlarged liver
  • Altered spleen
  • Decreased intestinal peristalsis
  • Stomach pain
  • constipation
  • diarrhea
  • Weight loss
  • Intestinal bleeding
  • Pain during urination
  • allergies
  • Weakness

When the genitourinary system is infected, patients experience:

  1. Menstrual disorders and miscarriages in women
  2. Impotence and incomplete ejaculation in men

When the eggs enter the central nervous system:

  • Acute cerebral schistosomiasis
  • Chronic brain damage
  • Fatal outcome

Infected children experience a slowdown in growth and development, reduced school performance. Disease prevention includes avoiding swimming and avoiding walking barefoot in tropical waters.


hand washing against parasites

Paragonim is a 1 cm long lung fluke with an ovoid body and red spines. This parasite multiplies in the lungs of animals and enters the human body by eating crabs, freshwater crabs. The parasite infects the respiratory system. Patients with paragonimiasis are characterized by allergic reactions and decreased immunity. symptoms:

  • Rising temperature
  • cough
  • Excretion of sputum from the lungs when coughing
  • dyspnea
  • In severe cases, the sputum contains blood and eggs of parasites.
  • Wheezing is clearly heard in the patient's lungs.
  • Prevention: Exclude the use of raw crabs and crabs.


Representatives of cestodes are tapeworms of different lengths. Some parasites reach gigantic sizes. On the head of these parasites there are suckers, hooks or suction slots. These adaptations are necessary for the parasites to adhere to the intestinal wall. Cestodes affect the entire human body, they are most dangerous for children who quickly develop anemia.


These parasites reach a length of 5 cm and are the causes of echinococcal disease. A multi-chambered representative of this type of worm is the cause of a disease such as alveococcosis. The disease is transmitted by cattle and domestic animals. When caring for these animals, the parasite's eggs fall from their fur into human hands. Upon entering the human intestine, the parasites bite into the mucosa. As the parasite matures, 4 sections appear, the last of which is filled with eggs. These compartments separate and spread throughout the body, infecting it. The fourth section spreads eggs all over the body.

Infected organ in a patient enlarges, for example, the liver. Suppuration may occur. An enlarged organ can even pierce the abdominal cavity. And this can lead to serious sepsis of the body and even death. symptoms:

  • Weakness
  • Dizziness
  • Allergic reactions to waste products of parasites.

Echinococcus affects:

  1. Brain
  2. Spinal cord
  3. Eyes
  4. thyroid gland
  5. Liver
  6. Lungs
  7. uterus

This parasite can provoke the formation of tumors, including malignant. The most unpleasant thing is that the treatment of this disease is possible only surgically. Prevention: personal hygiene in contact with animals.


These worms with an elongated body, round or in the form of a cylinder, parasitize most often in the body of children. These roundworms include pinworms, roundworms, hookworms.


Giardia in the human body

These are small white worms. The length of the female is 1 cm, the male is 0, 5 cm. These parasites have a pointed tail, which is why they were called pinworms. The habitat of pinworms is the human intestine. The front end of the parasite has a sucker, with the help of which a blade pierces the intestines, and the sharp end hangs down into the lumen and damages the walls. This disease is called enterobiosis. You can be infected by a person through dirty hands. There is a disease in preschool children attending kindergarten. Symptoms of pinworm infection include itching around the anus. Itching is more common at night when the female lays eggs while releasing a special substance. symptoms:

  1. Itching
  2. diarrhea
  3. Stomach pain
  4. headache
  5. Lack of appetite
  6. Prevention
  7. hand washing


These worms are the biggest. The length of the female is up to 0, 5 m. The female lays 200 thousand eggs a year, regardless of the male. The mechanism of infection is fecal-oral. Roundworm eggs enter the human body along with unwashed vegetables and fruits through dirty hands. The larva, which has entered the intestine, is selected from the shell and penetrates the intestinal wall as it migrates through the intestinal veins to the liver, through the hepatic veins to the heart, through the pulmonary arteries to the bronchi, then into the trachea and mouth. A partial number of larvae die in the open, the rest are swallowed back. symptoms:

  • nausea
  • Vomiting
  • jaundice
  • Pancreatitis
  • Common acute respiratory infections
  • Bronchitis
  • Pneumonia


  • hand washing
  • Washing vegetables and fruits
  • Personal hygiene
  • Protect food from flies, cockroaches and other traders.

In conclusion, we can say that the cause of the disease is not always bacteria and viruses that have entered the body. Parasites can cause great harm to human health. In case of unclear symptoms, it is not necessary to exclude the penetration of the parasite into the body, the patient should visit a parasitologist.