Protozoa are single-celled organisms that occur worldwide. Many of those that cause extraintestinal infections are transmitted by arthropod vectors. These arthropod-borne infections include African trypanosomiasis, babesiosis, Chagas disease, leishmaniasis, and malaria. Toxoplasmosis is acquired through contaminated food. Free-living amebas are acquired through contact with surface water or soil.
Last full review/revision January 2014 by Richard D. Pearson, MD
Content last modified January 2014