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 Antiquity to the Present
Common helminthiasis such as enterobiasis and ascariasis have been known for a long time.Human invasions by bovine tapeworms and roundworms were reported as early as the 16th century BC.BC reported in the ancient Egyptian medical treatise, 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, while studying 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 connection between the parasitism of the tapeworm in the human body and the occurrence of anemia in the patient.
A great contribution to the development and establishment of helminthology was made by an outstanding scientist and academician, who founded the first department of parasitology and opened specialized facilities for 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 also published over seven hundred scientific papers.
By the way, it is known that a parasitic infection worsens the course of concomitant diseases, especially chronic, decompensated ones.Helminth infections impair growth and the 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 major classes of helminths: tapeworms (cestodes), roundworms (nematodes) and flukes (trematodes).Nematodes are classified as roundworms, while tapeworms and flukes are classified as flatworms.Humans can act as intermediate or definitive hosts of parasites.
The causative agents of helminthiasis such as ascariasis, enterobiasis, trichinosis, hookworm disease, trichuriasis and strongyloidiasis are nematodes.Cestodes cause echinococcosis, alveococcosis, diphyllobothriasis, taeniasis, teniarinchiasis, hymenolepiasis, etc. And trematodes provoke opisthorchiasis, clonorchiasis, paragonimiasis, metagonimiasis and fascioliasis, among others.
Depending on the location of parasites in the body, there are:
- Luminal helminthiases.
- Tissue worm diseases.
- Hepatobiliary helminthiases.In this case, the parasitic infection affects the liver, gallbladder and bile ducts (opisthorchiasis, clonorchiasis).
- Pulmonary helminthiasis.
The following types of helminthiases are distinguished:
- Geohelminthiases.In this case, the parasite develops with the participation of an inanimate substrate (water, soil).
- Infectious helminthiasis.The development of worms occurs within a microorganism, for example in enterobiasis.
- Biohelminthiasis is the development of helminths involving intermediate hosts.A typical example is the broadband worm, which has a complex development cycle with host switching.
By the way, it was found that intestinal parasites in the body promote the release of Th2 cytokines, which suppress the Th1 cytokine.Therefore, people with helminthic infestations are at higher risk of becoming infected with a certain disease, such as tuberculosis.
Parasites in the body: main syndromes
The main clinical syndromes of helminth infections include:
Malnutrition syndrome
In the human body, the parasite is known to absorb nutrients from its host, which can cause the host 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 helminths remain in the body for a long period of time, they can have an immunosuppressive effect and reduce resistance to various microbial and viral infections.
Toxic-allergic organ damage
This involves a whole spectrum of diseases – of the heart (myocarditis), the liver (hepatitis), the lungs (pneumonia), and the brain (encephalopathy).Up to hemorrhagic necrotic 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.For example, hookworms and cestodes have a traumatic effect on the intestinal mucosa, opisthorchids damage the bile ducts, and schistosomes damage the mucous membrane 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 and Chinese flukes, can cause the development of carcinogenesis.This is evidenced by the so-called parasitic cancer theory.Chronic opisthorchiasis is particularly dangerous and can lead to cancer of the bile ducts in the long term.
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 when taking 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.
- Persistent dry cough (usually at night), in children – a persistent “barking” cough.
- An increase in the level of eosinophils in the blood is called eosinophilia.
- Anemia, especially B12 deficiency.
- Asthenic syndrome – general weakness, fatigue, malaise.Of course, such symptoms can be attributed to various diseases.However, if the child has an incomprehensible increase in fatigue or mood swings, poor sleep or nervousness, it makes sense to take a test for parasites.
If any of the above signs are present, this is a reason to consult a parasitologist or infectious disease specialist.