La toxoplasmose ≪ guyanaise ≫

In Europe and in the United States, toxoplasmo- sis is a benign infection except in case of severe immunodeficiency or of transplacental passage during early pregnancy. The human contamination is related to the domestic cycle of Toxoplasma gon- dii between the cat and meat producing animals such as sheep or pigs. The Toxoplasma strains are clustered only into three clonal lineages named types I, II and III, with a large predominance of type II in the human and animal infections. This "Western" vision of clinical, epidemiological and genetic aspects of toxoplasmosis should not occult the fact that Toxoplasma gondii is a parasite with a worldwide distribution. However, paradoxically, little is known about toxoplasmosis in vast and crowded areas such as South and Central America, Africa and Asia where clinical and epidemiologic specific features associated to particular strains could exist. In French Guiana, since ten years, tens of cases of life-threatening disseminated toxoplasmosis are described in immunocompetent patients. These severe forms, known locally under the name of "Guianese" toxoplasmosis, call into question the "Western" vision of an always benign infection in immunocompetent patients, related to a Toxo- plasma domestic cycle with only 3 clonal strains. Indeed, in the Guiana plateau, these severe forms are related to genetically atypical and diverse strains circulating in the Toxoplasma wild cycle of the Amazonian rainforest.