Helminthiasis is a large group of parasitic diseases caused by certain types of parasitic worms - helminths.Most helminthiases have similar clinical manifestations and therapeutic approaches.
Parasites: from ancient times to the present day
Such common helminthiasis as enterobiasis and ascariasis have been known for a long time.Human invasions by bovine tapeworms and roundworms were mentioned as early as the 16th century BC in the ancient Egyptian medical treatise: the Ebers Papyrus.Hippocrates himself paid great attention to helminths.It was they who introduced such concepts as "helminthiasis" and "ascariasis".
At the beginning of the 18th century, the German microbiologist Karl Rudolphi, studying a large number of animals, collected a whole collection of parasitic worms.Soon the science of parasitic worms appeared - helminthology.
In one thousand eight hundred and eighty-four, a famous scientist and doctor established a causal connection between the parasitism of tapeworm in the human body and the appearance of anemia in the patient.
An outstanding scientist and academician made a great contribution to the development and establishment of helminthology, 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 was directly involved.
Parasitologists have described more than five hundred species of parasitic worms previously unknown to science.The doctor himself discovered and described more than two hundred new species of helminths and 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, ability to work, and also have a depressing effect on the human immune system and nervous system.
Parasitic infection: types of worms
There are three large classes of helminths: tapeworms (tapeworms), roundworms (roundworms), trematodes (trematodes).Roundworms are classified as roundworms, while tapeworms and trematodes are classified as flatworms.A person can serve as an intermediate or definitive host of parasites.
The causative agents of helminthiases such as ascariasis, enterobiasis, trichinosis, hookworm disease, trichuriasis and strongyloidosis are roundworms.Tapeworms cause echinococcosis, alveococcosis, diphyllobothriasis, taeniasis, teniarrhiasis, hymenolepiasis, etc.And trematodes cause, among other things, opisthorchiasis, clonorchiasis, paragonimiasis, metagonimiasis, fascioliasis.
Depending on the location of parasites in the body, there are:
- Luminal helminthiasis.
- Tissue helminthiasis.
- Hepatobiliary helminthiasis.In this case the parasitic infection affects the liver, gallbladder and biliary tract (opisthorchiasis, clonorchiasis).
- Pulmonary helminthiasis.
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.The development of worms occurs inside a microorganism, as in enterobiasis.
- Biohelminthiasis is the development of helminths with the participation of intermediate hosts.A typical example is the large tapeworm, which has a complex development cycle with host changes.
By the way, it has been established that intestinal parasites in the body promote the release of Th2 cytokines, which suppress the Th1 cytokine.In this regard, people with helminth infestations have an increased risk of contracting a particular disease, for example, tuberculosis.
Parasites in the organism: 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 they remain in the body for a long time, helminths can have an immunosuppressive effect, reducing resistance to various microbial and viral infections.
Toxic-allergic organ damage
This is a whole spectrum of diseases: the heart (myocarditis), the liver (hepatitis), the lungs (pneumonia), the brain (encephalopathy).Up to necrotic hemorrhagic damage to internal organs.
Local damage to organ tissue
Most often it predominates in the chronic phase and is determined by the localization of the helminth.Thus, hookworms and tapeworms have a traumatic effect on the intestinal mucosa, opisthorchids damage the biliary tract, and schistosomes damage the mucosa of the large intestine and urinary tract.
By the way, it has been proven that helminth infections reduce the effectiveness of vaccination.Some helminths, for example, schistosomes, opisthorchids, Chinese trematodes, can provoke the development of carcinogenesis.This is demonstrated by the so-called parasitic theory of cancer.Of particular danger are 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 his body:
- Various types of allergic reactions, including unspecified recurrent urticaria, which does not disappear even with the use of hormonal and desensitizing drugs.
- Decreased or, conversely, increased 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 - a prolonged "barking" cough.
- An increased level of eosinophils in the blood is eosinophilia.
- Anemia, particularly vitamin B12 deficiency.
- Asthenic syndrome: general weakness, fatigue, malaise.Of course, such symptoms can be attributed to various diseases.However, if the child experiences an incomprehensible increase in tiredness or mood swings, poor night sleep or nervousness, it is appropriate to conduct a test for parasites.
If any of the above signs are present, this is a reason to consult a parasitologist or infectious disease specialist.