The simplest human parasites - the types and diseases they cause

The number of the simplest organisms living in the world's water bodies, soil and air is about 15, 000. Some are the oldest inhabitants of the planet. In the millions of years since the first living organism emerged, most protozoa have remained virtually unchanged. But they have learned to adapt to the new living conditions and to find ways to survive. One of the most obvious ways for these organisms to become parasitic, including the human body.

Parasitism

The fact that a parasite uses another organism as a habitat or food source is a kind of complex relationship between two living things.

The organism inhabited by the parasite is called the host. The parasite can be permanent when it passes through the entire period of development and in the interval, when the pathogenic organism passes only a certain stage of its life cycle.

Parasitism among protozoa is a type of interaction that not only lives and parasitizes at the expense of others, but also threatens the life of the host, as many types of parasites are present in humans, livestock, and agricultural crops.

The simplest human parasites have chosen almost all the organs and systems of the human body, are very active, and sometimes live for years. This symbiosis leads to chronicity of the disease and reduced effectiveness of the treatment process.

Ways to enter the body:

• through hands and mouth;
• through the skin;
• contact;
• transmission to the unborn fetus;
• by the bite of insects, animals;

A comprehensive science that studies the phenomenon of parasitism, the biology and distribution of parasites, their diagnosis, treatment and prevention of parasitic diseases.

The simplest pathogenic parasites that cause various diseases are found almost everywhere. These are fresh and salt water, soil, various household items and household items, public places. Protozoal infections are called protozoal or protozoan infections.

What are the simplest human parasites?

The human body, like the body of an animal more or less large, is a very attractive object for parasitic life patterns. Along with protozoa, multicellular parasites (helminths) can also live in the human body.

Depending on the habitat, the simplest species can be endogenous (living inside the human body) or exogenous (choosing the skin as a habitat). Sometimes, as they develop, parasites move throughout the body, choosing the most suitable habitat for a particular stage of development.

The microscopic size and primitive structure allow the simplest parasites to survive and reproduce successfully in the most difficult conditions. All members of this species are characterized by a single cell structure filled with intracellular fluid and cytoplasm, all metabolic processes occur in the presence of organelles (structures that perform various functions to maintain vital activity).

Movement functions can be performed by flagella, cilia, and pseudopodia designed for this purpose. The main process (cooking) is carried out in several ways:

• absorb from the cell mouth;
• walking with pseudopods (pseudopods);
• absorption by the membrane surface.

Adverse conditions can be a signal for the formation of cysts that are resistant to the external environment of the membranes. The simplest human parasites are needed to pass from one host to another, and can keep a captive inside the parasite for several years.

A reproductive cyst is characterized by the formation of a thin temporary shell, which is necessary for a protozoan for a short division period.

It is important!The simplest human parasites are the causes of protozoal infections: giardiasis, trichomoniasis, sleep disorders, amoebic dysentery, malaria.

Types of protozoan parasites

By reproduction and movement, by the nature of nutrition, there are 4 main classes of the simplest human parasites:

Flagellate

For example, lamblia, leishmania, trichomonas, trypanosomes. They have a long oval or pear-shaped body. They may have 1 to 8 thin cytoplasmic protrusions composed of the finest fibrils. It is as if they are advancing with a flag screwed into the space in front of them. They feed by absorbing both ready-made nutrients and through the membrane. Reproduction usually occurs by simple division into two daughter cells. Flagellates can live in a colony of up to 10, 000 people.

Sporozoans

For example, malaria plasmodia, Gondia toxoplasma. This protozoa is characterized by a very complex developmental pathway: from the carrier to human blood, then to the liver, where the parasite multiplies and affects red blood cells. Reproductive toxins cause diseases in the human home. For the next developmental period, pathogens must still enter the body where the male and female cells mature and spores form. After maturation, the spores are destroyed and the parasite re-enters the host's body. The period is repeated.

Ciliates

For example, balantidia. For ciliates, movement with the help of cilia is characteristic. There are two nuclei in the body's cell: the large nucleus controls all vital processes, and the small one plays a key role in the sexual side of the protozoan's existence. Reproduction occurs by dividing the cell in half, which for most species occurs several times a day. The food enters a special cavity (cell mouth) with the movement of the lashes, is processed by the digestive vacuole inside the cell, and the undigested residue is removed outside.

Sarcode

For example, amygdala is dysentery. It does not have a permanent shape, it forms many false fish, moves with their help and catches food. Multiplies by simple division. It can take several forms: tissue, luminal, precist. The tissue form lives only in the patient's intestines. The remaining forms can also be found on the body of the host.

It is important!Primary structure, cyst formation, the simplest way of reproduction, microscopic dimensions, all these factors allow the simplest parasites to penetrate the most protected tissues of the human body, and the number of serious and sometimes difficult to diagnose pathological conditions in the absence of adverse effects.

What diseases are caused by protozoan parasites

The parasitic lifestyle of the simplest microorganisms is facilitated by anaerobic respiration, although in addition to the above factors, many can use dissolved oxygen.

Diseases caused by protozoan parasites include:

Malaria

The main symptoms are fever attacks, joint pain, vomiting, anemia, convulsions. There may be enlargement of the spleen. Malaria is characterized by recurrent course of the disease, periods of rest and inflammation. Forms differ depending on the type of pathogen: three-day, four-day and tropical. The disease is common in Africa and South Asia. For centuries, as today, the mainstay of treatment is quinine made from the bark of the cinchona tree. Despite the creation of synthetic analogues, deaths from infection occur in areas that do not have access to modern medical care.

Amoebiasis (amoebiasis of dysentery)

The sarcoid is derived from the simplest parasitic amoeba of the dysentery class. The infection can be intestinal and extraintestinal (developing in the liver). The first symptoms appear 7-10 days after infection: abdominal pain, weakness, low-grade fever (up to +37. 5 ° C). About 10% may develop severe diarrhea with traces of blood and mucus. One in three infected people develops fever. It is characterized by enlarged liver and in some cases liver abscess. If treatment is not started on time, prolonged diarrhea can lead to thirst, weakness, and exhaustion. The spread of the disease is typical for countries with hot climates.

Giardiasis

The disease is the simplest cause of the flagellate lamblia class. These parasites have 4 pairs of flagella attached to the small intestine and a suction disc. Symptoms of infection include pain and swelling in the upper abdomen, rumbling and nausea, impaired bowel function, skin lesions (atopic dermatitis), abnormalities in gallbladder function, general weakness and loss of strength, poor appetite and sleep. Giardiasis is widespread in regions with hot climates in Asia, Africa and Latin America.

Leishmaniasis

The disease is caused by the parasite leishmania of the flag class. The main symptoms of skin and mucocutaneous leishmaniasis are skin lesions in the form of ulcers. Edema and deformity may occur with the mucocutaneous form. If the airway is blocked, it can rarely be fatal. The visceral form is characterized by enlargement of the liver and spleen, fever and anemia. The disease is prevalent in 88 countries, mainly in tropical and subtropical climates.

Trichomoniasis

The disease is caused by the flagellate parasite Trichomonas. The genitourinary system is affected. In women, the main symptoms may be itching and burning, hyperemia of the external genitalia, discharge with an unpleasant odor, and sometimes discomfort during sex and urination. In men, the disease is often asymptomatic, sometimes there may be pain during urination and discharge, signs of prostatitis.

Balantidiyaz

The causative agent is a parasite of the class balantidia siliates. Typical symptoms are abdominal pain, diarrhea and lining of the tongue. In acute cases of the disease, fever and general signs of intoxication are possible. The infection can also be chronic with periods of intermediate remission and exacerbation. In severe cases, intestinal perforation and peritonitis are possible.

Toxoplasmosis

The disease is caused by the Toxoplasma parasite of Gondia, a sporozoan parasite. Characteristic symptoms of the disease are damage to the eyes, nervous system, heart muscle, swollen lymph nodes, liver and spleen. Mainly chronic. Often the primary infection under the common name ARVI is very easy. After that, immunity develops forever and further infection is not possible. The greatest danger to the fetus during pregnancy: if the baby survives, it causes serious damage to the nervous system and eyes.

Sleep sickness

The disease is caused by the Gambia or Rhodes trypanosome, the simplest parasite of the flagellate class. In the first stage, the characteristic symptoms are fever, headache and joint pain. After 7-20 days, the second stage of the disease begins: disorders of perception of the surrounding world, disorders of coordination of movements, impaired coordination and sleep. The spread of the disease is localized in certain parts of tropical Africa, the habitat of the main vector of tsetse fly infection;

Chagas disease

The causative agent is a parasite of the flagella trypanosoma cruzi class. The main symptoms are fever, swollen lymph nodes, headache and swelling at the bite site. At the initial stage, the symptoms of the disease may disappear, and after 8-12 weeks in 30-40% may begin to develop secondary symptoms: an increase in the ventricles of the heart, enlargement of the esophagus, large intestine. The second stage of the disease can last 10-30 years after infection. The infection is most prevalent in Latin America.

It is important!Most of the simplest parasites enter the human body when the rules of sanitation and personal hygiene are not followed.

Ways of infection

Penetration of any microorganism into the human body can occur through the skin or natural cavities. For most of the protozoan parasites found in the environment, the methods of human infection are limited to the four most common methods:

1. Contact and home. This route of infection is accessible to the simplest organisms, violating the rules of sanitation and personal hygiene. After all, when most microorganisms pass from one host to another, they can form cysts and remain in that state until they enter a favorable environment, in other words, inside a person. Infection can occur at any time: when shaking hands, using other people's household items (towels, linen, dishes), washing hands with dirty water (in the pool);
2. Fecal-oral (giardiasis). In this case, the infection occurs when the parasite leaves the intestines with feces or vomit. If hygiene rules are not followed, the parasite enters the body of a new host by entering its water, food, or hands. Poorly washed vegetables and herbs can also be a source of infection, and dirty hands for children in a sandbox or after playing with pets;
3. Through contaminated foods (toxoplasmosis). The meat of most animals, especially wild animals, may contain cysts of protozoan parasites that enter the human body with adequate heat treatment. Infection is also possible through unsanitary dairy products and raw fish without adequate heat treatment;
4. Infectious (malaria, sleeping sickness). Infection occurs as a result of the transmission of the pathogen through the saliva of the carrier when bitten. The disease is transmitted directly by an infected insect to a sensitive organism.

In addition to the main methods of infection, infection can occur in several less common ways:

• Transplacental with the penetration of protozoa parasites from the infected placenta to the fetus;
• Hemocontact when parasite-infected blood enters the patient's body (during medical procedures, drug injections, sexual intercourse);
• Sexually transmitted infections occur only through sexual contact.

Prevention

Prevention of infection with protozoa parasites involves, first of all, the observance of all sanitary and hygienic rules. The exclusion of the possibility of parasite infection can be justified on the basis of a number of recommendations:

• Heat treatment of meat, dairy and fish products is sufficient (according to the heating mode according to the technology). Special attention is paid to products that have not passed sanitary control;
• Wash fruits, vegetables, berries and herbs thoroughly, preferably with boiling water. It is better to remove the skin, especially if heat treatment is not possible to feed children;
• Regular medical examinations, especially if there is a suspicion of infection with protozoan parasites;
• Adherence to a sexual partner and refusal to use drugs;
• Special measures can be taken to prevent infection from insect bites: the use of drugs, the destruction of mosquitoes, gnats and mosquitoes, the elimination of transgenic mosquitoes (resistant to malaria), the creation of vaccines.

It is important!The level of resistance of the organism is of great importance in the prevention of any infection, including the simplest human parasites. After all, if a cyst enters an unfavorable environment where it is not nourished or where immune cells are constantly attacking a foreign body, the parasite either dies or leaves the host's body.

There are many foods that contain natural immunostimulants (garlic, ginger, broccoli, carrots, green tea), when consumed in a balanced way, can be an invaluable aid in strengthening the body's immunity.

In addition, some products have a negative effect on the growth and reproduction of protozoa, especially those that inhabit the digestive system: rice and pearl barley porridge, dried fruits, baked apples, vegetable oil, baked vegetables. When treating parasites, it is necessary to limit or completely exclude products that cause fermentation processes: bakery products and sugar.

Currently, the pharmaceutical industry offers many expensive antiparasitic drugs. However, their effective use can be achieved only by taking preventive measures and following a certain diet, the composition of which can be consulted with a qualified specialist.

Do not forget about the time-tested and folk remedies of many generations. If all methods and techniques are combined under the supervision of a doctor, there will be very little chance of parasites.

The result

At the beginning of the 21st century, it can be said that mankind has achieved a lot in the development of parasitology. The message of a new discovery of a particular drug is always welcomed by people in need of help and treatment today.

The simplest human parasites are still a serious problem in many countries where the level of development of medicine and society as a whole is highly desirable. There are more places on our planet where malaria, sleeping sickness, leishmaniasis and many other diseases are spread. People expect and hope that everyone will have a chance to live without disease.

Today's parasitic diseases are relevant, require social interaction aimed at improving medical services to the population in all spheres of human life, compliance with the rules and norms of personal and public hygiene, preventive measures and sanitary-educational work, sanitary work. natural foci of pathogenic organisms.

At present, various scientific researches in the field of parasitology are carried out in many countries of the world:

• development of scientific bases and methods of monitoring of infectious and parasitic infections;
• study of biological characteristics and variability of the main diseases caused by protozoa parasites;
• control over the quality and environmental safety of meat and fish products;
• to conduct fundamental research to study the development of pathogens of parasitic diseases, their genetic variability and ecology.