Human protozoan parasites, despite their microscopic size, are some of the most dangerous microorganisms that can cause severe disease.
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 single cell with a certain shape, some can change it, the cell has organelles that support viability.Unicellular microorganisms have adapted to locomotion using cilia, flagella, or pseudopods.
Due to their small size and structural characteristics, protozoa can live even in the most protected tissues of the body.Parasites from the protozoan kingdom cause diseases of varying severity, some of them can even lead to death.
The removal of unicellular organisms is complicated by the fact that they are able to cover themselves with a protective shell (cyst) and wait for conditions unfavorable to their existence.
Classification of the simplest inhabitants of the human body
Unicellular parasites are divided into 4 classes, depending on the structure of the cell and the way of life.
Table "Classes and Representatives of Protozoan Parasites"
| Class | Brief description | Representatives |
| Whiplashes | The cells are oval in shape, have a flagellum for locomotion, move forward with a cord, thus able to penetrate deep into the liquid medium.Whip colonies can reach 10 thousand individuals.Most species live in tropical and subtropical climates. | Leishmania, Giardia, Trichomonas, Trypanosoma. |
| Sardcodae (rhizomes) | Movements are made with the help of pseudopods and have a variable body shape. | Dysenteric amoeba |
| Disputants | They got their name due to the presence of a spore stage in their development.Localized in tissues and cells, they can cause hepatitis or anemia. | Piroplasma, babesia, coccidia, falciparum plasmodium. |
| Ciliated | It moves with the help of cilia, can live attached or swim freely | Balantidium |
Depending on the location of localization, unicellular parasites are divided into 2 types:
- endogenous (live in internal organs and systems);
- exogenous (choose the skin as a place of residence).
Human protozoan parasites can move throughout the body and infect various organs and tissues.
What diseases do flagellates and cilia cause?
Order Whipples
- Leishmania causes cutaneous leishmaniasis (Pendinski's ulcer) and visceral leishmaniasis, the former manifesting as persistent festering sores 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 mucous membranes of the intestine or gall bladder.After the defeat, people begin to suffer from asthma, mental disorders (most often depression), 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 the 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 increase), cerebrospinal fluid, blood and spleen, as a result of which the functioning of the spleen and liver is disturbed, the patient suffers from drowsiness and may die.
A class of ciliates
Balantidia are the causative agent of balantidiasis affecting the lining of the large intestine.A clear sign of this parasite is diarrhea with mucus and blood.This disease often ends in death.
What diseases are caused by rhizomes and sporozoa?
Class Spores
- Plasmodium malariae enters the blood and liver and causes malaria.Symptoms of the disease are high fever, chills or fever, central nervous system disorders and death is possible.It is transmitted by the bites of malarial mosquitoes and is transmitted by humans.
- The causative agent of toxoplasmosis is toxoplasma, which affects the central nervous system, digestive organs, muscle tissue and eyes.Initially, it is asymptomatic, then disorders in the functioning of certain organs are observed.
Class sardcode
Dysenteric amoeba is the causative agent of amebiasis, affecting the lining of the large intestine and, less commonly, the bladder and skin.It can be asymptomatic or be signaled by vomiting, diarrhea with blood and subfebrile temperature (up to 37.5 degrees).Symptoms appear 7-10 days after the amoebae enter the body.
Less common are the extraintestinal forms of the disease, which affect the liver, lungs or other organs.This disease is common in Asian and tropical countries.
Routes of infection
Unicellular parasites enter our body in different ways - through the skin or natural openings in the human body.
There are four main ways (routes) of infecting a person with a parasitic disease:
- the contact-domestic route opens in case of unhygienic conditions and non-observance of personal hygiene rules (when shaking hands or using household items, bathing in dirty water, cysts enter the human body and begin to develop), trypanosomes and trichomonads are transmitted through this route;
- through products infected 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 hands of the owner and through them into the body of a new carrier (this route of infection is especially common in children: contact with animals, eating unwashed fruits, playing in a dirty sandbox);
- transmissible (malaria) - transmission of protozoan parasites through bites along with the carrier's saliva.
Much less often, parasites enter the body in the following ways:
- from the mother to the fetus during pregnancy, this path is called transplacental, since parasites penetrate the placenta;
- together with contaminated blood (blood transfusion and other medical procedures, injections, including narcotic ones, during intimacy) - blood contact;
- during intercourse - genital tract.
Prevention of infection
To prevent infection with unicellular organisms, one must follow a number of simple rules:
- proper heat treatment of fish and meat, control of milk;
- You can eat only those products that have passed a sanitary inspection;
- washing the fruit before eating and simply soaking it in water is not enough;you must wash them thoroughly and, if possible, pour boiling water over them;
- avoiding casual sexual contacts;
- prevention of insect bites (use of special creams, mosquito nets);
- regular medical examinations in case of suspected infection and for prevention;
- increasing immunity, including by consuming garlic, oranges, carrots, green tea, dried fruits, 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 of living unicellular parasites, helps to choose a priority among the listed preventive measures.
With proper prevention, and in case of illness - surgical treatment, the parasites will not harm your body.