Toxoplasma gondii is an obligate intracellular parasitic protozoan that can infect virtually all warm-blooded animals,including humans,and spread worldwide,causing a zoonotic parasitic disease known as toxoplasmosis.Toxoplasma gondii genotypes differ in different hosts in different areas or in the same area.Different genotypes of T.gondii strains have widely varying pathogenicity.This article describes the prevalence of different genotypes of T.gondii in different places around the world.