Among the simplest organisms there are many parasites of animals and humans.The parasitic protozoa that cause the most severe and common diseases are listed below.
Dysenteric amoeba
The dysenteric amoeba is similar to the common amoeba, but is smaller and has shorter and wider rhizomes.It enters the human digestive system through the mouth in the cyst stage.In the large intestine, the amoeba emerges from the cyst and feeds on bacteria without harming the person.After that, this simple organism begins to penetrate the intestinal wall, feed on red blood cells and become a parasite.Ulcers form in the intestines, which exhaust the human body.Amoebic dysentery or amebiasis occurs.
Dysenteric amoeba can enter the bloodstream and reach the liver.Here, too, the parasite leads to the creation of purulent ulcers.
Forming cysts, amoebas leave the human body with undigested food remains.Light cysts spread easily.If you don't wash your hands and food, you can get infected.
Plasmodium malariae
Plasmodium is a parasitic protozoan.Some species of Plasmodium cause malaria in humans.The malaria plasmodium vector is the malaria mosquito.During an insect bite, Plasmodium enters the host's bloodstream.Together with the blood, it reaches the liver, where it is fed, grows and reproduces.After that, many plasmodia re-enter the bloodstream and begin to parasitize red blood cells, destroying them and releasing their waste products, which poison the host.The person develops a fever and suffers from anemia.
If a person with malaria is bitten again by a malaria mosquito, the plasmodia will now be transmitted from the person to the mosquito.Plasmodium reproduces sexually in the mosquito's body.
Malaria is common in Africa.This is a very dangerous disease.The fight against malaria is conducted, among other things, by destroying the mosquitoes that transmit malaria.
Trypanosomes
The genus Trypanosomes consists of parasitic protozoa that have flagella (closely related to Euglena).Their main host is a vertebrate, and the carriers are usually insects.Different representatives of trypanosomes cause different diseases in animals and humans.They parasitize mainly in blood and cerebrospinal fluid.The best known and most common disease caused by trypanosomes is sleeping sickness.
The vector of sleeping sickness is the tsetse fly.This disease is typical of tropical Africa.Sleeping sickness develops in two stages: in the first weeks, a person suffers from fever and pain, after a month or more, drowsiness, sleep and coordination disorders, and changes in consciousness appear.The disease is easier to treat in the first stage.
Giardia
Giardia is a genus of flagellated parasitic protozoa.Intestinal lamblia in humans and animals causes giardiasis, in which the parasite lives in the small intestine.
A person becomes infected with giardiasis by eating unwashed food containing Giardia cysts.Emerging from the cyst, the lamblia attaches itself to the intestines and feeds on digested food.
Leishmania
Leishmania is another genus of parasitic protozoa.They cause leishmaniasis in humans and many other animals.Carriers are mosquitoes.
There are different types of leishmaniasis associated with damage to different tissues in the body.One of them is the skin disease Pendensky ulcer.
Coccidia
Coccidia are parasitic on many animals, including worms, arthropods and fish.They cause coccidiosis diseases, which cause serious damage in livestock and fish farming.
Coccidia settle in the form of spores containing parasite cells.
Coccidia include the genus Toxoplasma.Their representatives cause such a widespread disease in humans as toxoplasmosis.A person becomes infected from pets or poorly prepared meat food.Toxoplasma affects many organs, including the nervous system.