Parasitic diseases are a widespread, diverse group of diseases caused by helminths and protozoa that travel throughout the human body, feeding and reproducing with the aim of causing damage to organs and systems. different system. Due to their overall effect on the whole body, it is difficult to suspect and recognize them.
How does the infection take place?
Before entering the human body, helminths and protozoa go through a cycle of development in the environment or other living organism.
- Eggs and larvae of roundworms, strongyloides, hookworms still exist in the soil under certain temperature and humidity conditions. People become infected when contaminated soil enters through dirty hands, water, unwashed vegetables, and directly from the ground.
- In vivo, the following helminths undergo development cycles: opisthorchis (cat flukes), clonorchis, trichinella, toxocara, echinococcus, pork and bovine tapeworms. Before maturation, to parasitize in humans, one or two intermediate hosts can be changed. These are molluscs, crustaceans, fish, insects. Eating meat, processed fish with insufficient heat, raw water leads to infection.
Another route of infection is direct contact with people through handshakes, shared hygiene and household items, or by self-infection. We are talking about infectious helminths: trichiasis, strongyloidiasis, helminthiasis, giardiasis.
How can a parasitic disease be suspected?
Symptoms can vary widely, from mild to severe. Rarely, there are typical signs of a specific pathogen. Often there are no signs, either they disguise themselves as other diseases, or disappear when one cycle of parasite growth ends and another begins. For example, roundworm larvae first enter the human lungs, where they mature and migrate to the intestines. Children may be bothered by a brief cough (similar to a cold), which does not alarm parents.
However, the acute and chronic stages of the parasitic disease process are often distinguished.
Acute manifestations occur as a result of a general effect on the body:
- The effect of the poison - increased temperature up to 37 - 37. 5 degrees, weakness, headache, decreased mood and performance, sleep disturbances;
- Allergic reactions - pruritus, urticaria, bronchospasm, dyspnea, Quincke's edema less often;
- Activation of the immune system - muscle and joint pain; enlargement of the lymph nodes, liver and spleen;
- Mechanical effects - if viewed under a microscope, each helminth can see fixed devices in the body, damaging the mucosa: teeth, hooks, suction cups. The result is abdominal pain, frequent bowel movements, and indigestion.
The chronic stage is characterized by damage to several organs and systems. Usually, the intestines are affected, prolonged mechanical activity leads to inflammation, impaired ability to absorb and digest food. Anemia, lack of vitamins and minerals develop, in young children will be slow to grow, slow to gain weight. The gallbladder and biliary tract (giardia) may be affected; cardiovascular system, lungs, nervous system (usually trichiasis); lungs and liver (echinococcosis), v. v. With a long course, immunity is suppressed and secondary infections enter.
Therefore, we have many ways of infection, mechanism of development and manifestation of parasitic diseases. It turns out that every second person has a risk of disease, right? But sometimes the helminths may not stay in the body: die and go away, or "pass by" without starting the parasite (which is why detecting "worms" in the stool does not prove a cure). presence of disease). Much depends on the stage of the helminth, its invasive nature and the human immune system. More susceptible to helminth infections are children under 5 years of age, actively learning the world "on the tongue" and people with chronic diseases and weakened immunity.
If you find any of the listed signs, do a clinical blood test with a white blood cell count. Eosinophilia up to 7-10% or more would become another suspect criterion.
How to identify a parasitic disease?
- Fecal study for protozoa and helminth eggs, preferably enrichment method - PARASEP Identification of eggs of all helminths and intestinal protozoa
The criterion for disease activity is egg detection! This means the development of helminths in the body, its parasitism and reproduction. These are mainly intestinal worms which, when a person is the final host, are the "permanent residence" of the parasite, and the eggs are needed to spread further and start the next cycle.
You should pay attention to the following points:
- Each helminth species has its own developmental cycle, so a single study is not enough. If the results are negative, a triplicate study is recommended with an interval of 3-7 days;
- There are such forms of helminthiasis, where a person is an intermediate host (a carrier of the helminth larvae) or a "biological dead end", when the larvae have confused the host and cannot develop furtheragain. In such cases, eggs will never appear in the stool, the disease can only be detected by identifying antibodies.
- Check scraping for helminths - only pinworm eggs are found in the perianal folds. The female pinworm lays eggs, leaving the intestines only at night, when a person is relaxed. So the research is done strictly after sleeping Before washing!
- The study of lamblia antigens in feces is a highly accurate method for lamblia detection. For better detection, you should follow a healthy diet before the test.
- The study of antibodies to helminths (immunoglobulin) assesses the immune system against pathogens. Basically, the most persistent immunoglobulins are identified - class G (IgG), which reflects the reality of the infection, but it is not possible to understand if there are helminths in the body now, because IgG is stored inbody for a long time. time in "memory storage".
What should you pay attention to?
- The presence of simultaneous IgG manifestations and detection may indicate a chronic phase of helminthiasis;
- In case of doubt, the IgG test should be repeated after 2 weeks. An increase in the level of antibodies by 2 or more times indicates helminthic activity;
- For helminthiasis, coccidiosis, and fascioliasis, antibody determination is the only possible laboratory diagnostic method, since a person is an intermediate host of helminths. this.
For your convenience, a complex "Diagnosis of Parasites" has been developed, which includes clinical blood testing, total IgE (allergic component) and antibody determination to various helminthsand most common protozoa.