Human protozoan parasites, although microscopic in size, are one of the most dangerous microorganisms that can cause severe disease.
General information about representatives of protozoa
The kingdom of Protozoa has many representatives (about 15 thousand species), many of which are human parasites.
Another name for this kingdom, accepted in medicine and biology, is single-celled organisms.
This creature consists of one cell with a certain shape, something can change it, this cell has organelles that maintain its survival.Single-celled microorganisms have adapted to locomotion using cilia, flagella or pseudopods.
Due to their small size and structural features, protozoa can live in even the most protected body tissues.Parasites from the protozoan kingdom are agents that cause diseases of varying severity, some of which can even cause death.
Getting rid of single-celled organisms is complicated by the fact that they can be covered with a protective shell (cyst) and wait out conditions unfavorable for their existence.
The simplest classification of the inhabitants of the human body
Single-celled parasites are divided into 4 classes, depending on the cell structure and way of life.
Table “Classes and representatives of protozoan parasites”
| Class | Short description | Representative |
| Flagellates | The cells are oval in shape, have a flagellum for movement, move forward with ropes, so they can penetrate deep into the liquid medium.Flagellate colonies can reach 10 thousand individuals.Most species live in tropical and subtropical climates. | Leishmania, Giardia, Trichomonas, Trypanosoma. |
| Sardcodae (rhizopods) | Its movements are carried out with the help of pseudopods and have varying body shapes. | Dysentery amoeba |
| Sporozoa | They get their name because of the presence of a spore stage in their development.Localized in tissues and cells, they can cause hepatitis or anemia. | Piroplasma, Babesia, Coccidia, Plasmodium falciparum. |
| Ciliates | Moves with the help of cilia, can live attached or swim freely | Balantidium |
Depending on the location of localization, single-celled parasites are divided into 2 types:
- endogenous (lives in internal organs and systems);
- exogenous (chooses the skin as its residence).
Human protozoan parasites can move throughout the body and infect various organs and tissues.
What diseases do flagellates and ciliates cause?
Class Flagellates
- Leishmania causes cutaneous leishmaniasis (Pendinsky's ulcer) and visceral leishmaniasis, the first of which manifests itself as persistently rotting ulcers on the body, and the second causes inflammation and bleeding.Leishmania enters the body through warm-blooded animals or mosquito bites and affects the skin, heart, kidneys, blood and bone marrow.
- Giardia, the causative agent of giardiasis, affects the mucosal tissue of the intestine or gallbladder.After defeat, the patient begins 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.The biggest danger of this disease is the high risk of infertility.
- Trypanosomes cause African or American trypanosomiasis (the first is sleeping sickness, the second is Chags disease).It affects the lymph nodes (enlarge), cerebrospinal fluid, blood and spleen, as a result of which the function of the spleen and liver is impaired, the patient suffers from drowsiness and may die.
Ciliata Class
Balantidia is the causative agent of balantidiasis, which affects the mucous membrane of the colon.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?
Sporozoa class
- Malaria plasmodium enters the blood and liver and causes malaria.Symptoms of the disease are fever, chills or fever, problems with the central nervous system, and death can occur.This disease is transmitted through the bite of a malaria mosquito and is transmitted to 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 disturbances in the function of certain organs are observed.
Class sard code
Dysentery amoeba is the causative agent of amoebiasis, which attacks the mucous membrane of the colon, and less commonly, the bladder and skin.It may be asymptomatic, or it may be characterized by vomiting, diarrhea mixed with blood, and a mild fever (up to 37.5 degrees).Symptoms appear 7-10 days after the amoeba enters 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.
Routes of infection
Single-celled parasites enter our bodies in various ways - through the skin or natural openings in the human body.
There are four main ways (pathways) of transmission of parasitic diseases to humans:
- the contact-household route opens in case of unsanitary conditions and non-compliance with the rules of personal hygiene (when shaking hands or using household items, bathing in dirty water, cysts enter the human body and begin to develop), trypanosomes and Trichomonas are transmitted along this route;
- through products contaminated with parasites (meat, especially wild animals, fish, dairy products), can be disinfected using 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 very common in children: contact with animals, eating unwashed fruit, playing in a dirty sandbox);
- infectious (malaria) – transmission of protozoan parasites through bites along with the carrier's saliva.
Less commonly, parasites enter the body in the following ways:
- from mother to fetus during pregnancy, this route is called transplacental, because the parasite penetrates the placenta;
- together with contaminated blood (blood transfusions and other medical procedures, injections, including narcotics, during intimacy) - blood contact;
- during sexual intercourse - sexual 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, dairy control;
- You should only eat products that have passed sanitary inspection;
- washing the fruit before eating, and simply dipping it in water is not enough;You need to wash it thoroughly and, if possible, pour boiling water over it;
- avoid casual sexual contact;
- prevention of insect bites (use of special creams, mosquito nets);
- regular health checks for suspected infections and prevention;
- increasing immunity, including through consumption of garlic, oranges, carrots, green tea, dried fruit, rice porridge;
- basic knowledge about which protozoa parasitize the human body and how they get there.
Following these rules is easy, the main thing is regularity.
Information about parasite groups, examples of where single-celled parasites live, helps to choose priorities among the mentioned preventive measures.
With proper prevention, and in case of illness - surgical treatment, parasites will not harm your body.