The world health organization (who) reports that more than 4.5 billion people are infected with parasites. A parasite is an ancient representative of the natural world. According to the latest reports, the parasites have existed on Earth even before the appearance of man: some hole in the skull of tyrannosaurs, probably the result of infection with the parasite Trichomonas type, which can leave scars on the bone tissue.
Different types of parasites that can occur along with the man and at his expense, raises some diagnostic and therapeutic difficulties.
Type of parasite
Parasites (from the Greek para, about, and sito, food; παράσιτος, parasites live at the expense of others) is a living organism live in (endoparasite) or on (ectoparasites) a second organism. The parasite can be fixed, obliges, through the entire life cycle, staying in a host (another organism), and use it only in certain stages, the so-called interim or discretionary parasitism. Some of the parasite throughout the life cycle of the host, began the development together with the body and ends in another. That is, some parasitic organisms alongside the host only for a certain period of time, changing owners, or exist independently of the rest of the time, others begin and end their life cycle in one body.
The phenomenon of parasitism observed on all levels of life. There are intracellular parasites, the simplest form of multicellular parasites, parasites of plants, parasites live inside or on the outer part of multicellular organisms.
The purpose of the introduction of the parasite is to obtain nutrients, for safety, obtain the necessary development environment. Parasitic organisms can impair the quality of life of the owner, cause irritation, affect the dysfunction, ruin the fabric and also excrete toxins, promote the development of diseases. It is believed that the parasite evolyutsioniruet in the direction of decreasing harm to the host organism, thereby extending the opportunity to be at his expense.
In a separate category out of the parasite: as a rule, with two wings or Hymenoptera insects laid eggs in the bodies of animals or insects, provides the larvae with food. With the birth of larvae to the host will die, becoming food for new parasites. Activity of parasites is characterized by a combination of parasitism and predation.
This parasite are, for example, the emerald wasp stings cause partial paralysis and subordinate behavior of a cockroach. Then the wasp deposits an egg in the body of the insect and carries it into the hole. Hatching larvae eat the cockroach. Some insects so parasites honed the skills of parasitism, that colonize the host and affect its behavior for a long time. The larvae of several species of organisms-owners parasites, Glyptapanteles (wasp-rider) to protect hatched larvae of the enemy, as well as being food for them.
Classic parasitism is a special case of symbiosis, the coexistence of the two organisms. Such a common residence may be beneficial to the host and the parasite to harm one of the participants or the process happen without much influence. Different life forms, including parasitism, it is sometimes difficult to draw a clear line. For example, some forms of helminths to reduce the sensitivity of the human body to allergens, at the same time, causing damage and affect the conditionally positive health of the owner. Also known as hirudotherapy, the use of leeches for medical purposes – an ancient form of treatment for various diseases, is used as one of the methods of alternative medicine in today's world.
Can parasitize bacteria, insects, plants, birds... for Example, the cuckoo refers to a kind of "nest or eggs of the parasite", because it brings the eggs into the nests of other birds. The same behaviour have some other birds and fish and insects. Certain varieties of plants, such as broomrape, are root parasites growing on the roots of the plants and fed at the expense of other plants. The famous chaga mushroom, used in medicine, is a parasite growing on trunk of birch.
Numerous types of parasites – protozoa, helminths and insects. These parasites in the human body and on its surface is common.
Parasites in the human body
Parasites in the human body can be quite varied: the simplest life forms, viruses, fungi, worms, bacteria. In accordance with the classification of viruses (intracellular parasites) and bacteria are also parasitic species, but more often, speaking about parasites in the human body, referring to protozoa and helminths.
A long history of coexistence of people of helminths is confirmed by archaeologists: as soon as possible to find helminth eggs in the feces in 5 years from 900 BC. Written evidence has come down to us of the Ancient Egyptian papyrus in 3000 BC to store the information about the round worms, pinworms, tapeworms.
Hippocrates and Aristotle also drew attention to the parasites of fish, meat, tracing during development, for example, the pork tapeworm. The first mention of malaria belongs to the Emperor of China, Qin Shi Huans, which described the symptoms 2 year 700 BC.
The surface of the body and external organs of humans can be parasites, they are called parasites (Ectoparasites). Ectotrophic parasites – multicellular organisms, the best-known blood-sucking insects (lice of various species, ticks), some species of leeches also belong to the Ectotrophic mind a temporary parasite of the common man.
Mind parasites in the human body can be quite diverse. The parasites, their eggs and waste can be performed by mechanical impact, clog capillaries, vessels, ducts of glands. Some can chew through the intestinal wall, damaging tissue. The most negative impact on health, causing violation of certain functions of the body in varying degrees.
As parasites, protozoa are the simplest forms of life. 17 species of protozoa that can cause disease in humans. They are so exotic, that the Russian species such as Trypanosoma brucei, laptop infected tsetse fly. Trypanosoma brucei causes sleeping sickness or African trypanosomiasis characterized by confusion and sleep disturbance. The disease is most often found in the tropics of Africa, the Congo basin and Russia is extremely rare. Amoebiasis, caused by dysentery amoeba, is the second death master human parasitic disease in the world, it affects every tenth inhabitant of the Country. The most common is amoebiasis in regions with tropical climate and poor sanitary conditions.
Malaria is also caused by parasites carried by an infected mosquito. According to statistics, every year fall ill from malaria to 250 million people.
The most common in the world three types of protozoan parasites – Giardia (giardiasis disease), Toxoplasma gondii (toxoplasmosis) and Trichomonas (trichomoniasis).
Giardiasis – a disease of childhood
Giardiasis was first described by Dr. D. F. Lampl, which will detect Giardia cause. In accordance with the statistics of the world health organisation's annual infection lamblia is made about 200 million people on Earth. When sick giardiasis long-about 500 million people.
In russia, the data show that 100 thousand population, clinical signs of disease 90 people, but if you separate the sick children up to 14 years, of which 100 thousand children giardiasis is diagnosed 350. Thus, in Russia Giardiasis are more prone to child, most frequently ages 1 to 4 years.
Giardia has two forms: moving, or vegetative, and form cysts. Infection occurs by ingestion of cysts, which may persist in the environment (soil) up to 3 weeks, and the water-up to 5.
Infection occurs most often in children, when to lick the dirty hands, as well as household goods, as well as the use of vegetables, fruits, berries, not heat-treated. Extended also getting Giardia in the body along with the infected cysts water.
Once in the body, moving from Giardia to form cysts grow and multiply in the small intestine, causing irritation. Specific symptoms of giardiasis generally is not clear, limiting such signs, a violation of stool (diarrhea, constipation), biliary dyskinesia, pain in the upper part of the stomach and the navel, nausea, atopic dermatitis, General malaise. Sometimes there is a delay, weight and height of the child.
After moving to the small intestine to the large intestine Giardia lose a favorable environment for reproduction, transformirovalsya again cysts and the environment together with the feces.
For the treatment of giardiasis consists of regenerative medicine of the digestive tract, the parasites of this species and to improve the immune system. The risk of infection is good personal hygiene, handling products and before eating, drinking raw water exclusively sanitized form.
Toxoplasmosis is a dangerous disease during pregnancy
The simplest one-celled parasite Toxoplasma gondii, causing toxoplasmosis, responsible for the emergence of the myth that women during pregnancy should not touch the cat – the baby is born ugly.
Toxoplasma gondii is a parasite do, that the temporary host using the felines. Its increase is possible only in the intestine of these animals, and most foods are cats. Toxoplasma eggs excreted in the feces of an infected animal, and can get in the body of the other Pets and farm animals or people through contact with feces, contaminated soil, eating raw meat. Toxoplasma gondii belongs to such intracellular parasites, these samples is one of the smallest parasites of the Earth.
Cats are the primary host of Toxoplasma, an organism in which the parasite spends most of its life cycle. The bodies of other warm-blooded animals, including humans, Toxoplasma gondii uses a limited time.
Studies have shown that Toxoplasma gondii can affect the behavior of the infected animal. Thus, rodents with toxoplasmosis feel a little fear, before cats: parasites control the behavior of rats and mice, to "push" the master transmission of Toxoplasma the body where it can multiply.
The parasite reproduces in the tissues of heart, liver, eyes, brain. According to the world health organization (who), every third person is ill or sick with toxoplasmosis.
The disease occurs in several forms. A normal immune disease is easily tolerated is manifested in the growth of uterine cervical and axillary lymph nodes, periodic low fever, muscle aches, General malaise. A mild form of toxoplasmosis spontaneously without specific treatment.
Chronic toxoplasmosis is involved to change the structure of the eye. The acute form is manifested in a rash, sudden deterioration of health, leading to exhaustion, can cause encephalitis, the brain. As a rule, the development of acute toxoplasmosis usually people with severe immune deficiency.
Infection with toxoplasmosis during pregnancy leads to transmission of infectious agents through the placenta to the fetus. Toxoplasma in this case, the cause of congenital toxoplasmosis in the newborn, which lead to blindness, disorders of the central nervous system, jaundice, abnormalities of the skull bones, mental retardation. Congenital toxoplasmosis in children can occur immediately, symptoms may appear months or years after birth.
The man, who was ill with toxoplasmosis develops immunity, is defined as the presence of antibodies in the blood. If a pregnant woman has no history of the disease toxoplasmosis during pregnancy, she is recommended to remove contact with cat faeces and avoid places of possible accumulation of the rodents.