Diseases Caused By Protozoa: Infections in Humans due to Protozoans

Protozoan Infections in Humans

Protozoa are single cell, living microorganism. They have structures like flagella and cilia which help them in their movements. Almost all the humans, some time in their life time must have got infected with protozoa. Some of the disease caused by protozoa can be mild to life threatening.

Protozoan Diseases in Humans

Some of the important protozoan diseases are:

  • Malaria: it is mosquito -borne tropical disease caused by the plasmodium species of protozoa. The various types of species are P. vivax, P. falciparum, P. ovale, P.malariae. The organism enters the body in the form of sporozoites injected by female anopheles mosquito during a blood meal.
    The sporozoites are transported to liver where they mature.
  • Symptoms manifested are fever with rigors, followed by excessive sweating followed by thirst for water. The liver and spleen are enlarged on palpation. Patient looks anemic. Malaria is most dangerous infectious disease all over the world.
  • Amoebiasis: it is a disease caused by infection of the tissues with a protozoan Entamoeba histolitica. It is characterized by gastrointestinal and constitutional symptoms. It runs a chronic course with periodic episodes of acute exacerbations. It can cause amoebic dysentery, amebic liver abscess. The symptoms A. dysentery is lose and watery stools, with griping pain in the abdomen.
    A. liver abscess may cause fever with chills, pain in the right side of the abdomen.
  • Giardiasis is caused by giardia lambia, a flagellate protozoon. It causes diarrhea which varies in severity.
  • African sleeping sickness: ┬áit is caused by Trypanosoma Brucei, it is transmitted to man by the bite of TseTse flies. The disease is more prevalent in Western Africa. The symptom begins with fever, joint pain and headache, sleepiness during the day and insomnia at night, coma and death.
  • Toxoplasmosis: it is caused by toxoplasma gondii. It is caused by eating infected meat, or unwashed vegetables. The symptoms are similar to flu. It can be a fatal cause if found in an AIDS patient.