Echinococcus In Humans: Life Cycle, Symptoms And Treatment

Table of contents:

Echinococcus In Humans: Life Cycle, Symptoms And Treatment
Echinococcus In Humans: Life Cycle, Symptoms And Treatment

Video: Echinococcus In Humans: Life Cycle, Symptoms And Treatment

Отличия серверных жестких дисков от десктопных
Video: Echinococcus (causative agent, life cycle, transmission, symptoms & treatment) 2023, February
Photo echinococcus structure
Photo echinococcus structure

What is a disease such as echinococcosis ? The disease is caused by parasitic worms - hydatid echinococcus, belonging to a variety of tapeworms. Helminths inhabit the intestines of dogs and cats. Echinococcus in humans develops as a result of the ingestion of the eggs of the parasite. The danger is not the adults, but the larvae of the echinococcus. Helminth affects people of all ages, but the disease is especially dangerous in children and the elderly. Infection is a serious danger for the simple reason that the disease can be secretive for several years.


  1. Echinococcus life cycle
  2. How can you get infected with echinococcus?
  3. Symptoms of the disease depending on the location of the lesion: liver, lungs, brain, kidneys and heart
  4. Liver
  5. Lungs
  6. Brain
  7. Kidney
  8. A heart
  9. Analyzes
  10. Treatment

Echinococcus life cycle

At the first stages, the helminth does not develop in the human body. He is an intermediate host for echinococcus. Deer and moose, and domestic ungulates - cows, sheep, goats and pigs - also act as such a host.

Echinococcus cycle
Echinococcus cycle

The main host of echinococcus is canines (dogs, wolves), sometimes cats. The development cycle is represented by the following chain:

  • Helminth develops in the intestines of canines. They excrete the eggs of the parasite along with the feces. The eggs fall into the ground. Dried helminths are carried by the wind over considerable distances, penetrating into the soil and water. The larvae can remain on the dog's coat, where they get when the dog licks the anal area, and then the coat;
  • The eggs enter the body of an intermediate host - a person who becomes infected by contact with cats and dogs, or by eating unwashed vegetables containing echinococcus eggs;
  • Through the oral cavity, helminth eggs enter the stomach, where they lose the shell that covers them. As a result, the larvae go out and enter the bloodstream, penetrating into it through the walls of the stomach or intestines. They are then carried by the bloodstream throughout the body;
  • Then the larvae penetrate into any organ and are fixed on its walls. Bubbles begin to form around them, cysts appear;
  • Migrating through the body, the parasite penetrates into other parts of the body, causing disease of the liver, heart and lungs, spinal cord and brain and other organs.
  • The life cycle of a helminth in animals (cats, foxes, dogs) is the same. The final owner of echinococcus becomes infected after swallowing meat containing larvae or sniffing the stool of a sick animal;
  • The life cycle of the parasite ends after a full-fledged individual, ready for reproduction, grows from the scolex (worm).

How can you get infected with echinococcus?

Infection occurs through contact with sick animals (dog or cat). The parasite can be found on their fur. When stroking a pet, helminth eggs can go to the skin of the hands, and from there to the mouth area and further into the body.

echinococcus infection
echinococcus infection

The causes of the disease can be systematized in the form of a table:

The reasons Infection routes Who is most often affected by the disease
violation of hygiene rules. · Lack of washing hands after contact with pets (cats and dogs) or after gardening (after contact with soil);

· Consumption of meat, beef and pork liver, which contains echinococcus;

· Eating unwashed greens, vegetables and fruits.

· Owners of dogs (in rare cases and cats), as well as hunters.

· Pastoralists;

· Reindeer herders;

· Residents of areas with weak veterinary control.

Echinococcus is not transmitted from person to person by contact and everyday life. Airborne infection is possible only in areas prone to epidemics.

Symptoms of the disease depending on the location of the lesion: liver, lungs, brain, kidneys and heart

The pathogen affects various organs and systems. In one case, the larvae, attached to the walls of the organ, form single bubbles, in the other, multiple formations (cysts). Differences in the course of the disease are due to the fact that there are several varieties of helminths - echinococcosis and alveolar echinococcosis.

With alveoccosis, the growths penetrate the blood vessels and behave like pathological cancer cells, spreading metastases deep into tissues and organs.

The disease has several stages of its course:

  • first (latent);
  • the second (mild);
  • third (symptoms of the disease are pronounced);
  • fourth (characterized by the presence of complications).

The rate of transition of the disease from one stage to another depends on the location of the parasite in the body.

A single bubble grows slowly and at first is not felt in any way. The first symptoms of the disease appear when an overgrown cyst begins to interfere with the functioning of the affected areas.

Each organ has its own characteristic symptoms of the course of echinococcosis. The methods of treatment are also individual.


In the liver, unicameral echinococcosis most often develops. In rare cases, a multi-chamber is formed.

liver echinococcus
liver echinococcus


  • First stage. General weakness, fatigue appear, allergic reactions are possible, an increase in body temperature. On palpation, an enlargement of the liver is felt, pain appears, the liver tissue becomes denser;
  • The second stage is characterized by the appearance of nausea and vomiting, a violation of the stool, the abdomen increases in size, pain appears in the liver area;
  • The third stage - severe symptomatic pains appear in the right hypochondrium, body temperature rises, jaundice may develop, ascites (accumulation of fluid in the abdominal cavity), a stable increase in body temperature;
  • Fourth stage. At this stage, the echinococcal blisters may rupture and the infection gets into the peritoneal area, peritonitis (inflammation), anaphylactic shock will appear. As a complication, purulent intoxication of cystic growths may appear, accompanied by the appearance of severe pain in the liver.


Echinococcosis of the lungs, as a rule, is unicameral. Until the third stage of the disease, symptoms are not observed. When the bubble reaches a large size, an echinococcal cyst of the lung appears, the disease is characterized by:

  • the appearance of dull pain in the lungs, coughing and shortness of breath;
  • swelling of the cyst;
  • an increase in body temperature up to 39 ° C;
  • breakthrough of the cyst into the peritoneum, pleura, bronchi, pericardium, biliary tract. The development of anaphylactic shock as a consequence of this, the appearance of asphyxia (suffocation), insemination of tissues with echinococcosis.


In the early stages, there are no symptoms, then there are signs characteristic of those that cause brain parasites in humans, these include:

  • seizures of epilepsy;
  • increased intracranial pressure;
  • headache;
  • there are cuts in the limbs;
  • hallucinations occur;
  • delirium appears;
  • nausea and vomiting;
  • depression develops;
  • dementia appears.

Echinococcus affecting the brain can be both single-chamber (single formations) and multi-chamber (the appearance of cystic clusters, with a protective capsule of inflamed brain tissue).


Echinococcus usually affects both kidneys at once. The helminth attaches to the crust or penetrates into the peri-renal tissue.

The nature of the lesion is multi-chamber (there is practically no single chamber). Symptoms are not expressed. There may be pain in the lumbar region. If the bladder breaks, the infection spreads further through the body, and the patient may develop renal colic.

With a complication of the disease, acute pyelonephritis may develop, parts of the bladder membranes or hooks are revealed in the urine, with which the worm is attached to the tissues.

A heart

Echinococcus rarely affects the heart. In the first stages, it is asymptomatic. Then appear:

  • arrhythmia;
  • heart failure;
  • pain in the sternum.

If the bladder breaks, signs of cardiac tamponade appear (accumulation of fluid in its tissues, disrupting its work), circulatory embolism (the presence of particles in the bloodstream - an embolus).


Before the necessary treatment is prescribed, research is carried out:

  • blood test for echinococcus;
  • ultrasound procedure;
  • Magnetic resonance imaging;
  • CT scan;
  • x-ray.

To detect the presence of helminths in the blood, blood serum is examined by ELISA (Enzyme Immunoassay). It detects the presence or absence of antibodies to echinococcus.


If titers for echinococcus are not detected in the blood, but symptoms of the disease are observed, further studies of all organs and systems in which the parasite may be present are prescribed.


Echinococcosis is almost always treated with surgery. The reason is late seeking medical help. In this case, the cyst is removed, or it is opened and its contents are removed.

Drug therapy with pills is used when there are small single cysts. This is how the echinococcus of the liver and other organs is treated. Antihistamines and antiparasitic drugs are prescribed (Gelmadol, Mebendazole, Nemozole).

Echinococcosis is a dangerous disease fraught with serious complications that can lead to death. It is easier to prevent it than to cure it. Therefore, you need to observe hygiene measures: wash your hands thoroughly after interacting with animals, handle food well, eat clean vegetables and fruits.

Taking vitamins and drugs that strengthen immunity, adherence to a healthy lifestyle, and a healthy nutrition system helps to increase the body's defenses and resist the effects of worms.

Popular by topic