Specific diseases classified as infectious include parasitosis. They are caused by specific parasites that adapt to life in or on the human body, feed and reproduce there or with its help. At this time, a person can be both an intermediate and a definitive host for parasites (that is, either eggs and larvae or adults develop in the body). Depending on the type of parasites and the location of the lesion, many diseases caused by them can be identified. The most common are helminthiasis - diseases caused by parasites of specific types of worms.
Parasites: different types of helminths in the body
The largest group of parasites that can live in the human body are various types of worms, both flat and round. They belong to a separate group of diseases that doctors collectively call "helminthoses". Each parasite of this group has its own way and methods of infection, life cycle characteristics and development of clinical manifestations, as well as its treatment methods. In addition, each parasite is capable of causing specific complications according to its life cycle. The most common parasites that can make people sick are pinworms and roundworms, trichinella, pork or cattle tapeworms.
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 parasite species lives in the human 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 they affect. For this, it is important to undergo a complete examination and pass a number of tests. Why is this necessary?
First of all, it should be remembered that different types of parasites live in the body of the host as a larva (if a person is their intermediate host) or in a sexually mature individual (if it is a final host). In this regard, depending on the stage at which the worm is parasitized, the therapeutic effects can be different, as well as the habitat of the parasite.
Parasite species such as Exinococcus will be dangerous to humans in the larval stage. The larvae, which are in the form of a round cyst capsule filled with a poisonous liquid, infect the lungs, liver, kidneys or brain. Within these organs, over months or years, an echinococcus cyst grows, which contains larvae. However, parasitic species such as pinworms live in the body as sexually mature individuals. Females exit the rectum to lay millions of eggs, which are released into the environment in the feces.
Depending on the type of parasites, as well as the individual reactions of the body to them, the location of the lesion and the reaction of the body, clinical manifestations range from asymptomatic to acute and severe, even fatal. It should also be remembered 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?
Parasites can enter the body in different ways. Infection often occurs when parasite eggs enter the human body with contaminated food or water, from dirty hands, as well as through damaged skin, insect bites. Often, worm eggs remain in the form of eggs for a long time in the soil, water or on the surface of things. Entering the body through hands, food, or untreated water, parasites penetrate the body, where the eggs quickly mature and hatch into larvae (intermediate versions of the parasite) or adults.
It should be remembered that parasites in the body cause serious harm, even if there are no obvious signs of damage. First, they eat the host, depriving it of certain 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 products and substances that were previously quite familiar.
The body is not indifferent to the penetration of worms, especially if it is soft tissue and internal organs. Thus, protective inflammatory capsules are formed in muscles and tissues that separate the parasite from healthy tissues. This often leads to the formation of parasitic cysts filled with the waste products of the worms. Often, the body reacts to the introduction of parasites with digestive disorders, if these are worms living in the intestines, changes in appetite, weight fluctuations and exacerbation of chronic diseases.
Do not think that the problem of parasites is relevant only for people from the poorest countries and those who do not pay attention to the issue of hygiene. The prevalence of helminths is amazing, according to the WHO, it can be compared with diseases such as ARVI and influenza. Therefore, it is necessary to undergo regular examinations and exclude parasitosis.
What parasite test is needed?
Many patients mistakenly believe that a negative parasite test (stool or perianal smear) is a guarantee that they are free of parasites. But in reality, everything is not like that, and this result means nothing. First, parasites can be extraintestinal, living in other organs and tissues, and their eggs or larvae do not simply end up in the feces.
Second, when testing for parasites, there may be a period when the parasite is still not laying or laying eggs. Thirdly, there is a risk that all the conditions for the analysis are not met, and therefore the eggs were simply not found in the sample presented.
Therefore, if we are talking about intestinal worms, when a test for parasites is prescribed, stool is taken three times at a certain interval to confirm the presence of parasites. Only this technique can confirm or deny the diagnosis with a probability of up to 90%.
More indicative in this regard is the analysis of parasites taken from a vein with the determination of antibodies against certain worms. If the body has been in contact with the parasite very recently, it will have M-class antibodies to identify the pathogen. Prolonged presence of the parasite will also produce antibodies of other classes.