Helminthiasis is a large group of parasitic diseases caused by certain types of parasitic worms - helminths.Most helminthiases have similar clinical manifestations and treatment approaches.
Parasites: from ancient times to the present day
Common helminthiases such as enterobiasis and ascariasis have been known for a long time.Human invasions of bovine tapeworms and nematodes were mentioned as early as the 16th century BC.C. in a medical treatise from ancient Egypt: the Ebers papyrus.Hippocrates himself paid great attention to helminths.It was they who introduced concepts such as "helminthiasis" and "ascariasis".
At the beginning of the 18th century, the German microbiologist Karl Rudolphi, during the study of a large number of animals, collected a whole collection of parasitic worms.Soon the science of parasitic worms appeared - helminthology.
In 1884, a famous scientist and doctor established a causal relationship between the parasitism of the tapeworm in the human body and the appearance of anemia in the patient.
A great contribution to the development and establishment of helminthology was made by an outstanding scientist and academician, who organized the first department of parasitology and opened specialized institutions dedicated to the study of helminths.On his initiative, more than three hundred parasitological expeditions were carried out, in which he participated directly.
Parasitologists have described more than five hundred species of parasitic worms that were previously unknown to science.The doctor himself discovered and described more than two hundred new species of helminths, and also published more than seven hundred scientific articles.
By the way, it is known that parasitic infection worsens the course of concomitant diseases, especially chronic and decompensated ones.Helminth infections negatively affect growth, working capacity, and also have a depressing effect on the human immune and nervous system.
Parasitic infection: types of worms
There are three major classes of helminths: tapeworms (cestodes), roundworms (nematodes), and trematodes (trematodes).Nematodes are classified as roundworms, while tapeworms and flukes are classified as flatworms.A person can act as an intermediate or definitive host for parasites.
The causative agents of helminthiasis such as ascariasis, enterobiasis, trichinosis, hookworm, trichuriasis and strongyloidiasis are nematodes.Cestodes cause echinococcosis, alveococcosis, diphyllobothriasis, taeniasis, taeniarynchiasis, hymenolepiasis, etc.And trematodes cause, among other things, opisthorchiasis, clonorchiasis, paragonimiasis, metagonimiasis, fascioliasis.
Depending on the location of the parasites in the body, there are:
- Luminal helminthiases.
- Tissue helminthiases.
- Hepatobiliary helminthiases.In this case, the parasitic infection affects the liver, gallbladder and bile ducts (opisthorchiasis, clonorchiasis).
- Pulmonary helminthiases.
The following types of helminthiasis are distinguished:
- Geohelminthiasis.In this case, the parasite develops with the participation of a non-living substrate (water, soil).
- Contagious helminthiasis.Worm development occurs within a microorganism, as in enterobiasis.
- Biohelminthiasis is the development of helminths with the participation of intermediate hosts.A typical example is the broad tapeworm, which has a complex development cycle with host change.
By the way, it has been found that intestinal parasites in the body contribute to the release of Th2 cytokines, which suppress the Th1 cytokine.In this sense, people with helminthic infestations have a higher risk of becoming infected with a certain disease, for example, tuberculosis.
Parasites in the body: main syndromes.
The main clinical syndromes of helminth infections include:
malnutrition syndrome
It is known that the parasite, while in the human body, consumes nutrients from its host, which can cause the latter to develop protein-energy deficiency, hypovitaminosis and anemia.This often happens when the body is damaged by tapeworms and roundworms that parasitize the intestines.
Immunosuppressive syndrome
When remaining in the body for a long time, helminths can have an immunosuppressive effect, reducing resistance to various microbial and viral infections.
Allergic-toxic organ damage
These are a whole spectrum of diseases: the heart (myocarditis), the liver (hepatitis), the lungs (pneumonia), the brain (encephalopathy).Up to hemorrhagic necrotic damage to internal organs.
Local damage to organ tissue.
Very often it predominates in the chronic phase and is determined by the location of the helminth.Thus, hookworms and cestodes have a traumatic effect on the intestinal mucosa, opisthorchids damage the biliary tract, and schistosomes damage the mucous membrane of the large intestine and urinary tract.
By the way, helminth infections have been shown to reduce the effectiveness of vaccination.Some helminths, for example, schistosomes, opisthorchids and Chinese flukes, can cause the development of carcinogenesis.This is evidenced in the so-called parasitic theory of cancer.Of particular danger is long-term chronic opisthorchiasis, which can ultimately lead to cancer of the biliary tract.
When should you see a doctor?
The following may indicate that a person has parasites in their body:
- Various types of allergic reactions, including unspecified recurrent urticaria, which do not go away even with the use of hormonal and desensitizing drugs.
- Decrease or, on the contrary, increase in appetite.
- Exhaustion of the body.
- Itching in the anal area, especially in the evening or at night.
- Dyspeptic phenomena.
- Unstable stools: diarrhea or constipation.
- Prolonged dry cough (usually at night), in children - prolonged "barking" cough.
- An increase in the level of eosinophils in the blood is eosinophilia.
- Anemia, especially B12 deficiency.
- Asthenic syndrome: general weakness, fatigue, malaise.Of course, these symptoms can be attributed to various diseases.However, if the child has an incomprehensible increase in fatigue or bad mood, lack of sleep at night or nervousness, it makes sense to perform a parasite test.
If any of the above signs are present, this is a reason to consult a parasitologist or infectious disease specialist.