Human protozoan parasites, despite their microscopic size, are one of the most dangerous microorganisms that can cause severe disease.
General information about representatives of protozoa
The kingdom Protozoa has a large number of representatives (about 15 thousand species), most of which are human parasites.
Another name for this kingdom, accepted in medicine and biology, is single-celled organisms.
This creature consists of a cell of a certain shape, some can change it, cells have organelles that maintain viability.Single-celled microorganisms have adapted to locomotion using cilia, flagella or pseudopods.
Due to their small size and structural features, protozoa can live even in the most protected body tissues.Parasites of the protozoan kingdom are the causative agents of diseases of varying severity, some of which can 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 for unfavorable conditions for their existence.
Classification of the simplest 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 | Brief description | representative of the people |
| Flagellates | The cells are oval in shape, have flagella for movement, move forward with a cord, thus being able to penetrate deeply 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) | Movement is carried out with the help of pseudopods and has a variable body shape. | Amoeba dysentery |
| Sporozoa | They got their name because of the presence of a spore stage in their development.Localized in tissues and cells, it can cause hepatitis or anemia. | Piroplasmas, 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 (choose the skin as their habitat).
Human protozoan parasites can travel throughout the body and infect various organs and tissues.
What diseases are caused by flagellates and ciliates?
Class Flagellates
- Leishmania causes cutaneous leishmaniasis (Pendinsky's ulcer) and visceral leishmaniasis, the first of which manifests itself as a constant festering ulcer on the body, and the second of which 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 mucous tissue of the intestine or gallbladder.After the defeat, people began to suffer from asthma, mental disorders (most often depression), and the skin became dry.Giardia is common in countries with warm climates.
- Trichomonas (depending on the habitat - mouth, intestine 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 biggest danger of this disease is the high risk of infertility.
- Trypanosoma causes African or American trypanosomiasis (the first is sleeping sickness, the second is Chags disease).It affects the lymph nodes (they enlarge), cerebrospinal fluid, blood and spleen, as a result of which the function of the spleen and liver is disturbed, the patient experiences drowsiness and may die.
Class Ciliates
Balantidia is the causative agent of balantidiasis, which affects the mucous membrane 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 Sporozoan
- Plasmodium malaria enters the blood and liver and causes malaria.Symptoms of this disease are fever, chills or fever, central nervous system disorders, and death is possible.It is spread through the bite of malarial mosquitoes and is spread 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 disturbances in the function of certain organs are observed.
class sardcode
Dysenteric amoeba is the causative agent of amoebiasis, affecting the mucous membrane of the large intestine, and more rarely, the bladder and skin.It may be asymptomatic, or it may manifest itself in vomiting, bloody diarrhea, and low-grade fever (up to 37.5 degrees).Symptoms appear 7-10 days after the amoeba enters the body.
Less common is the extraintestinal form of the disease, which affects the liver, lungs or other organs.This disease is common in Asian and tropical countries.
Route of infection
Single-celled parasites enter our bodies in different ways - through the skin or natural openings in the human body.
There are four main ways (routes) of human infection with parasitic diseases:
- the contact-household route is opened in case of unsanitary conditions and non-compliance with 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 trichomonas are transmitted through this route;
- through products contaminated with parasites (meat, especially wild animals, fish, dairy products), they can be disinfected using heat treatment;an example of a disease spread in this way is toxoplasmosis;
- fecal-oral route: the parasite leaves the body with feces or vomit, then enters water, food, household items, the owner's hands, and passes through it into the body of a new carrier (this route of infection is very common among children: contact with animals, eating unwashed fruit, playing in a dirty sandbox);
- transmissible (malaria) - transmission of protozoan parasites through bites together with the carrier's saliva.
More rarely, parasites enter the body in the following ways:
- from mother to fetus during pregnancy, this route is called transplacental, because the parasite penetrates through the placenta;
- together with contaminated blood (blood transfusions and other medical procedures, injections, including narcotics, during intimacy) - blood contact;
- during sexual intercourse - sexual channel.
Infection prevention
To avoid infection with unicellular organisms, one must follow a few simple rules:
- proper heat treatment of fish and meat, milk control;
- You can eat only products that have passed the hygiene inspection;
- washing fruits before eating, and just dipping them in water is not enough;you need to wash it thoroughly and, if possible, pour boiling water over it;
- avoid casual sexual relations;
- prevention of insect bites (use of special creams, mosquito nets);
- regular medical examination for suspected infections and for prevention;
- improve immunity, including through the use of 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 very easy to follow these rules, the main thing is regularity.
Information about parasite groups, for example where single-celled parasites live, helps to choose priorities among named preventive measures.
With proper prevention, and in case of disease - surgical treatment, parasites will not harm your body.