Specific diseases classified as infectious include parasitism. They are caused by special parasites that have adapted to live in or on the human body, feeding and reproducing in it or with its help. In this case, an individual can be both an intermediate and a definitive host for parasites (ie either eggs and larvae or adults develop in the body). Depending on the type of parasites and the location of the damage, many diseases caused by them can be identified. The most common are helminthiasis - diseases resulting from parasitism of specific types of worms.
Parasites: various types of helminths in the body
The largest group of parasites that can live in the human body are various types of worms, flat and round. They belong to a separate group of diseases, which doctors collectively call "helminthiasis". Each parasite of this group has its own routes and methods of infection, characteristics of the life cycle and the development of clinical manifestations, as well as methods of its treatment. In addition, each parasite is capable, due to its life cycles, of causing specific complications. The most common parasites that can make people sick are tapeworms and roundworms, trichinella, pork or bovine tapeworm.
Types of parasites and characteristics of the course of infection
If there are indirect signs of helminth infection, it can be assumed that one of the types of parasites lives in the person's body. However, for the treatment to be effective and correct, it is important to know the specific types of parasites, as well as which organs and systems are affected by them. To do this, it is important to undergo a full examination and pass a number of tests. Why is this necessary?
First of all, it is important to remember that different types of parasites live in the body of the host in the larval state (if a person is its intermediate host) or in a sexually mature person (if the final host). In this regard, the therapeutic effects, depending on the stage that the worm parasitizes, can be different, as well as the habitat of the parasite.
Types of parasites such as echinococcus will be dangerous to humans in the larval stage. The larvae, in the form of a round cyst capsule filled with toxic fluid, infect the lungs, liver, kidneys or brain. Within these organs, for many months or years, an echinococcus cyst develops, inside of which there are larvae. But such types of parasites as pinworms live in the body in the form of sexually mature individuals. Females crawl out of the rectum to lay millions of eggs, which are released into the external environment in the feces.
Depending on the type of parasites, as well as the individual reactions of the organism to them, the location of the lesion and the response of the organism, the clinical manifestations range from asymptomatic to severe and severe, even fatal. It is also worth remembering that there are variants of mixed infections, when several types of parasites live in the body at the same time.
How do parasites enter the body?
The ways of entry of parasites into the body can be different. Infection often occurs when parasite eggs enter the human body with contaminated food or water, from dirty hands, as well as from damaged skin, through insect bites. Often, worm eggs remain for a long time in the form of eggs in the soil, water or on the surfaces of objects. Entering the body through the hands, food or water that has not been properly treated, the parasites penetrate the body, where the eggs quickly mature into larvae (intermediate versions of the parasite) or adults.
It is important to remember that parasites in the body cause serious damage, even if there are no obvious signs of damage. First of all, they eat their host, depriving it of some nutrients, vitamins and minerals. In addition, parasites in the body sharply increase the allergenicity of the body, overstimulate the immune system, which threatens the development of spontaneous skin and other allergic reactions to previously well-known products and substances.
The body does not remain indifferent to the penetration of worms into it, especially if it concerns soft tissues and internal organs. Thus, protective inflammatory capsules are formed in muscles and tissues, separating the parasite from healthy tissues. This leads to the formation of parasitic cysts, often filled with worm waste. Often the body also reacts to the introduction of parasites with digestive disorders, if it is worms that live in the intestines, changes in appetite, weight fluctuations and exacerbation of chronic diseases.
Don't think that the pest problem only concerns people from poorer countries and those who don't care about hygiene. The prevalence of helminths is amazing; according to the WHO, it is comparable to diseases such as ARVI and influenza. Therefore, it is necessary to undergo regular examinations and to rule out parasitism.
What kind of pest control is needed?
Many patients mistakenly believe that a single test for parasites (stool or smear from the perianal area), showing a negative result, is a guarantee of the absence of parasites in the body. However, in reality, not everything is like this, and this result does not mean anything. First, the parasites may be extraintestinal, living in other organs and tissues, and then their eggs or larvae simply do not end up in the feces.
Second, at the time of testing for parasites, there may be a period of the parasite's life that is still or no longer laying eggs. And thirdly, there is a risk that all the conditions for the analysis will not be met and therefore the eggs will simply not be found in the sample provided.
Therefore, if we are talking about intestinal worms, when a test for parasites is prescribed, the stool is taken three times in a certain interval to confirm the presence or absence of parasites. Only this technique can confirm or refute the diagnosis with a probability of up to 90%.
More indicative in this regard is an analysis for parasites taken from a vein, with the determination of antibodies to certain worms. If the body has been in contact with the parasite very recently, there will be class M antibodies in it, which will identify the pathogen. Long-term presence of the parasite will also produce antibodies of other classes.