Parasitic diseases are a widespread, diverse group of diseases caused by helminths and protozoa that go through the life cycle in the human body, feeding and reproducing at the expense of the "host" and causing damage to various organs and systems. Given the effect on the whole body as a whole, it is quite difficult to suspect and recognize them.
How does the infection occur?
Before entering the human body, helminths and protozoa go through a developmental cycle in other environments or living organisms.
- Roundworm eggs and larvae, strongyloids, wormwicks remain in the soil under certain conditions of temperature and humidity. A person becomes infected when contaminated soil enters through contaminated hands, water, unwashed fruits and vegetables, directly from the soil.
- In living organisms, the following helminths undergo developmental cycles: opisthorchis (wild meat), clonorchis, trichinella, toxocara, echinococcus, pork, and bovine tapeworm. Before reaching maturity, to parasitize on a person, it is possible to change one or two intermediate hosts. These are mollusks, crustaceans, fish, insects. By eating insufficiently thermally processed fish and meat, raw water leads to infection.
Another way of infection is through direct contact of people through handshake, common hygiene and household items, or through self-infection. We are talking about contagious helminths: enterobiasis, fortyloidosis, cysticercosis, giardiasis.
How can a parasitic disease be suspected?
Manifestations can be varied, from mild to severe. Rarely are there typical signs that give a specific pathogen. Often there are no signs, either they are disguised as other diseases, or they disappear when one cycle of parasite development ends and another begins. For example, ascaris larvae first enter the human lungs, where they mature and migrate to the intestines. The child may be bothered by a brief cough (similar to a cold), which does not alarm the parent.
However, acute and chronic stages of the parasitic disease course are usually distinguished.
Acute manifestations occur as a result of a general effect on the body:
- Effects of toxins - a rise in temperature to 37 - 37. 5 degrees, weakness, headache, decreased mood and performance, sleep disturbances;
- Allergic reactions - itching, urticaria, bronchospasm, shortness of breath, rarely Quincke's edema;
- Activation of the immune system - muscle and joint pain; enlarged lymph nodes, liver and spleen;
- Mechanical impact - if you look under a microscope, any helminth can see attachments to the body, damaging the mucosa: teeth, hooks, suction cups. The result is colic, frequent bowel movements and indigestion.
The chronic phase is characterized by damage to several organs and systems. Most often, the intestine suffers, prolonged mechanical action leads to its inflammation, impaired absorption and digestion. Anemia, a lack of vitamins and minerals develops, and in young children there is a delay in growth and weight gain. The gallbladder and biliary tract (giardiasis) may be affected; cardiovascular system, lungs, nervous system (usually trichinosis); lungs and liver (echinococcosis) etc. With a long course, immunity is suppressed and secondary infections join.
So we have many ways of infection, mechanisms of development and manifestations of parasitic diseases. It turns out that every second person is at risk of getting sick, right? But sometimes helminths may not stay in the body: they die and leave, or pass "in transit" without beginning to parasitize (this is why the discovery of a "worm" in the feces does not prove the presence of the disease). Much depends on the stage of the helminth, its invasive properties and the human immune system. Most susceptible to the development of helminthiasis are children under 5 years, actively learning the world "in language" and people with chronic diseases and weakened immunity.
If you find any of the signs listed, do a clinical blood test with a leukocyte count. An increase in eosinophils of up to 7-10% or more will become another questionable criterion.
How to identify a parasitic disease?
- Fecal examination for protozoa and helminth eggs, preferably enrichment method - PARASEP Determines eggs of all types of helminths and protozoa living in the gut
The criterion for disease activity is the detection of eggs! This means the passage of the helminth development cycle in the body, its parasitism and reproduction. These are mainly intestinal helminthiasis, when a person is the last host, the "permanent residence" of the parasite and the eggs are needed for further spread and the start of the next cycle.
You should pay attention to the following points:
- Every helminth has its own development cycle, so a single study is not enough. If the result is negative, a three-time study with an interval of 3-7 days is recommended;
- There are such forms of helminthiasis when a person is an intermediate host (carrier of helminth larvae) or a "biological dead end" when the larvae have confused the host and can not develop further at all. In such cases, the eggs will never appear in the feces, the disease can be detected only by the determination of antibodies.
- Itching examination for enterobiasis - detects only worm eggs in perianal folds. Female worms lay eggs, leaving the intestines exclusively at night, when a person is relaxed. Therefore, the study is carried out strictly after bedtime Before bathing!
- The study of lamblia antigen in feces is a high-precision method for lamblia detection. For best detection, it is recommended to adhere to a choleretic diet before testing.
- The study of antibodies to helminths (immunoglobulins) aims to assess the immune system against pathogens. Basically, the most persistent immunoglobulins are determined - class G (IgG), reflecting the fact of infection, but not making it possible to understand whether there is a helminth in the body now or not, as IgG is stored in the body for a long time"memory archive".
What should you pay attention to?
- The presence of manifestations and simultaneous detection of IgG may indicate a chronic stage of helminthiasis;
- In suspicious cases, it is recommended to review IgG after 2 weeks. An increase in the level of antibodies by 2 times or more indicates helminth activity;
- With trichinosis, echinococcosis, cysticercosis, antibody determination is the only possible method of laboratory diagnosis, as a person is an intermediate host for these helminths.
For your convenience, a complex "Diagnosis of parasitic diseases" has been formed, including a clinical blood test, total IgE (allergic ingredient) and determination of antibodies to the most common helminths and protozoa.