The protozoa are transmitted by protozoa diseases. Despite being free-living organisms, in most cases, some protozoa are parasites of animals and humans. Amebiasis, Giardiasis, Malaria, Chagas disease are some of these protozooses.
The parasites are usually transmitted by water and food contaminated by feces, which contain the cysts of these microorganisms.
Cysts are an inactive form, which allows protozoa to resist for long periods in the environment, being activated in the host’s body.
Malaria is an exception, as the protozoan is transmitted by the bite of an insect. The greatest occurrence of these diseases is in poor countries, where basic sanitation and efficient water treatment are lacking. In addition, the lack of hygiene habits contributes to dissemination.
Chagas disease
Contamination occurs mainly by eating food contaminated with the insect’s feces.
It can also be through blood transfusion, transplantation of contaminated organs or even be transmitted from the mother to the baby during pregnancy (congenital).
It is estimated that in Brazil about 3 million people have this disease. Caused by Trypanossoma cruzi , which is a flagellated protozoan that parasites wild animals like the armadillo.
Another species of this protozoan causes sleeping sickness , which is very common in Africa. About 95% of cases are caused by Trypanossoma brucei gambiense , which occurs in central and western Africa. There is also Trypanosoma brucei rhodesiense , in eastern and southern Africa.
Malaria
Caused by different species of plasmodium-type protozoa, the most common in Brazil is Plasmodium vivax.
The malaria is transmitted to humans through the bite of the mosquito genus Anopheles. It can also be transmitted by blood transfusion.
Malaria still kills hundreds of thousands of people worldwide today. Especially in poor countries, where there is less investment in research to eradicate the disease.
Amebiasis
The transmission of the disease occurs mainly through the ingestion of water or food contaminated by feces containing amoeba cysts. It can also be sexual, through oral-anal contact, but this is more rare.
The amoebiasis and amoebic dysentery is caused by pathogenic amoeba called Entamoeba histolytica . It occurs a lot in poorer countries, estimating that 50% of people are infected each year.
Giardiasis
The infection occurs both by eating contaminated water and food, as well as by direct contact of the hands with objects contaminated by the cysts.
The causative agent of giardiasis is the flagellated protozoan Giardia lamblia , whose cysts are eliminated in the feces of infected people.
Trichomoniasis
The trichomoniasis is a sexually transmitted disease caused by Trichomonas vaginalis. It is commonly transmitted between partners who do not use adequate protection (condoms) and can affect both men and women.
Toxoplasmosis
Toxoplasmosis is a disease caused by the protozoan Toxoplasma gondii found in the feces of cats.
The human being is contaminated by consuming meat from birds and mammals that are rare and with the cysts of the parasites.
The disease can also be congenital, resulting from the mother’s infection during pregnancy.