Human protozoan parasites, despite their microscopic size, are one of the most dangerous microorganisms that can cause serious diseases.
General information about representatives of protozoa.
The kingdom of protozoa has a large number of representatives (about 15 thousand species), many of which are human parasites.
Another name for this kingdom, accepted in medicine and biology, is unicellular organisms.
These creatures consist of a cell of a certain shape, some can change it, the cell has organelles that maintain viability.Unicellular microorganisms have adapted to locomotion using cilia, flagella or pseudopodia.
Due to their small size and structural characteristics, protozoa can live even in the most protected tissues of the body.Parasites from the kingdom of protozoa are agents that cause diseases of varying severity, some of which can even cause death.
Getting rid of single-celled organisms is complicated because they can cover themselves with a protective layer (cyst) and wait for unfavorable conditions for their existence to pass.
Classification of the simplest inhabitants of the human body.
Unicellular parasites are divided into 4 classes, depending on cell structure and mode of life.
Table “Classes and representatives of protozoan parasites”
| class | Brief description | Representatives |
| flagellated | The cells are oval in shape, they have a flagellum for movement, they advance with a cord, thus being able to penetrate deeply into the liquid medium.Colonies of flagellates can reach 10 thousand individuals.Most species live in tropical and subtropical climates. | Leishmania, Giardia, Trichomonas, Trypanosoma. |
| Sardcodae (rhizopods) | The movements are performed with the help of pseudopodia and have a variable body shape. | Dysenteric amoeba |
| Sporozoans | They got their name due to the presence of a spore stage in their development.Located in tissues and cells, they can cause hepatitis or anemia. | Piroplasmas, Babesia, Coccidia, Plasmodium falciparum. |
| ciliates | It moves with the help of cilia, it can live attached or swim freely. | Balantidium |
Depending on the location, unicellular parasites are divided into 2 types:
- endogenous (lives in internal organs and systems);
- exogenous (they choose the skin as a place of residence).
Human protozoan parasites can move throughout the body and infect various organs and tissues.
What diseases are caused by flagellates and ciliates?
class flagellates
- Leishmania causes cutaneous leishmaniasis (Pendinsky ulcer) and visceral leishmaniasis, the former manifesting as constantly rotting ulcers on the body and the latter causing inflammation and bleeding.Leishmania enters the body through warm-blooded animals or a mosquito bite and affects the skin, heart, kidneys, blood and bone marrow.
- Giardia, the causative agent of giardiasis, affects the mucosal tissues of the intestines or gallbladder.After the defeat, people begin to suffer from asthma, mental disorders (most often depression), and the skin becomes dry.Giardia is common in countries with hot climates.
- Trichomonas (depending on the habitat: oral, intestinal and genital or urogenital), causes trichomoniasis.After infection, a person feels itching in the area of the reproductive system, and pathological discharge from the genitals is observed.The greatest danger of this disease is the high risk of developing infertility.
- The trypanosome causes African or American trypanosomiasis (the first is sleeping sickness, the second is Chags disease).It affects the lymph nodes (they enlarge), the cerebrospinal fluid, the blood and the spleen, so the functioning of the spleen and liver is altered, the patient suffers drowsiness and may die.
ciliate class
Balantidia is the causative agent of balantidiasis and affects the mucous membrane of the large intestine.A clear sign of this parasite is diarrhea with mucus and blood.This disease usually causes death.
What diseases are caused by rhizomes and sporozoans?
class of sporozoans
- Malaria plasmodium enters the blood and liver and causes malaria.Symptoms of the disease are fever, chills or fever, central nervous system disorders, and death is possible.It is transmitted through the bite of malaria mosquitoes and is carried by humans.
- The causative agent of toxoplasmosis is toxoplasma, which affects the central nervous system, digestive organs, muscle tissue and eyes.At first it occurs without symptoms, then alterations in the functioning of certain organs are observed.
sardinian class code
Dysenteric amoeba is the causative agent of amoebiasis and affects the mucous membrane of the large intestine and, less commonly, the bladder and skin.It may be asymptomatic or may manifest with vomiting, diarrhea mixed with blood and low-grade fever (up to 37.5 degrees).Symptoms appear 7 to 10 days after the amoebas enter the body.
Less common are extraintestinal forms of the disease, which affect the liver, lungs or other organs.This disease is common in Asian and tropical countries.
Infection routes
Single-celled parasites enter our body in different ways: through the skin or natural openings in the human body.
There are four main ways (pathways) of human infection with a parasitic disease:
- the contact-home route opens in case of unsanitary conditions and non-compliance with the rules of personal hygiene (during handshakes or using household items, bathing in dirty water, cysts enter the human body and begin to develop), trypanosomes and trichomonas are transmitted through this route;
- through products contaminated with parasites (meat, especially wild animals, fish, dairy products), they can be disinfected by heat treatment;An example of a disease transmitted in this way is toxoplasmosis;
- fecal-oral route - parasites leave the body with feces or vomit, then enter water, food, household items, the owner's hands, and through them into the body of a new carrier (this route of infection is especially common among children: contact with animals, eating unwashed fruits, playing in a dirty sandbox);
- transmissible (malaria): transmission of protozoan parasites through bites along with the saliva of the carrier.
Much less frequently, parasites enter the body in the following ways:
- from the mother to the fetus during pregnancy, this path is called transplacental, since the parasites penetrate through the placenta;
- together with contaminated blood (blood transfusion and other medical procedures, injections, including narcotics, during intimacy) - contact with blood;
- during sexual intercourse - sexual tract.
Infection prevention
To prevent infection with single-celled organisms, a person must follow a number of simple rules:
- adequate heat treatment of fish and meat, milk control;
- Only those products that have passed the health inspection can be consumed;
- Washing fruits before eating them and simply soaking them in water is not enough;it is necessary to wash them well and, if possible, pour boiling water over them;
- avoidance of casual sexual contacts;
- prevention of insect bites (use of special creams, mosquito nets);
- periodic medical examinations to detect suspected infection and for its prevention;
- increase immunity, including by consuming garlic, oranges, carrots, green tea, dried fruits and rice porridge;
- basic knowledge of which protozoa parasitize the human body and how they get there.
It is easy to follow these rules, the main thing is regularity.
Information about groups of parasites, examples where single-celled parasites live, helps to choose the priority among the mentioned preventive measures.
With proper prevention and, in case of illness, surgical treatment, parasites will not harm your body.