Among the simplest organisms are many parasites of animals and humans.The parasitic protozoa responsible for the most serious and common diseases are listed below.
Dysenteric amoeba
The dysenteric amoeba is similar to the ordinary amoeba, but it is smaller and its root stems are shorter and wider.It enters the human digestive system through the mouth at the cyst stage.In the large intestine, the amoeba emerges from the cyst and feeds on bacteria without harming the person.Subsequently, this simple organism begins to penetrate the intestinal wall, feeds on red blood cells and becomes a parasite.Ulcers form in the intestines, depleting the human body.The disease is amoebic dysentery, or amoebiasis.
The dysenteric amoeba can enter the bloodstream and reach the liver.Here, too, the parasite leads to the formation of purulent ulcers.
Forming cysts, amoebae leave the human body with undigested food debris.Mild cysts spread easily.If you don't wash your hands and eat, you can become infected.
Malaria plasmodium
Plasmodium is a parasitic protozoan.Some species of Plasmodium cause malaria in humans.The carrier of the malaria plasmodium is the malaria mosquito.During an insect bite, the plasmodium enters the host's bloodstream.With the blood, it reaches the liver, is nourished there, grows and multiplies.After this, many plasmodia enter the bloodstream again and begin to parasitize the red blood cells, destroying them and releasing their waste products which poison the host.A person develops a fever and suffers from anemia.
If a person with malaria is bitten by a malaria mosquito again, the plasmodia will now be transferred from the person to the mosquito.Plasmodium reproduces sexually in the body of a mosquito.
Malaria is common in Africa.It is a very dangerous disease.We fight malaria, among other things, by destroying malaria-carrying mosquitoes.
Trypanosomes
The Trypanosomes genus is made up of parasitic protozoa with flagella (close to Euglena).Their main host is a vertebrate animal and their carriers are generally insects.Different representatives of trypanosomes cause different diseases in animals and humans.They mainly parasitize the blood and cerebrospinal fluid.Sleeping sickness is the best known and most common disease caused by trypanosomes.
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 is tormented by fever and pain, after a month or more drowsiness appears, sleep and coordination disorders, and changes in consciousness.The disease is easier to treat at the first stage.
Giardia
Giardia is a genus of flagellate parasitic protozoa.Intestinal lamblia causes giardiasis in humans and animals, in which the parasite lives in the small intestine.
A person becomes infected with giardiasis by eating unwashed food that contains Giardia cysts.Having emerged from the cyst, lamblia attaches 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.The carriers are mosquitoes.
There are different types of leishmaniasis associated with damage to various tissues in the body.One of them is the skin disease Pendensky ulcer.
Coccidia
Coccidia parasitize many animals, including worms, arthropods and fish.They cause coccidiosis diseases, which cause serious damage to livestock and fish farming.
Coccidia are deposited in the form of spores containing parasitic cells.
Coccidia include the genus Toxoplasma.Their representatives cause such a widespread disease in humans as toxoplasmosis.A person becomes infected through pets or poorly prepared meat foods.Toxoplasma affects many organs, including the nervous system.