Molecular characterization of environmental Cryptococcus neoformans isolates in Jos, Plateau State, Nigeria

The members of the Cryptococcus neoformans/Cryptococcus gattii species complex comprise the most common fungal pathogens that causes fatal central nervous system infections in both humans and in a wide range of mammals. Cryptococcosis, an AIDS-defining disease has a huge burden in sub-Saharan Africa. Bird excreta are considered an environmental reservoir for Cryptococcus neoformans in urban areas. Therefore a study aimed at isolating and characterizing the yeast is important in disease management. One hundred samples of pigeon guano were collected within the city of Jos, Plateau State, Nigeria. Cryptococcus neoformans was isolated from three samples and initially identified using standard phenotypic and biochemical tests. Molecular analysis, based on a specific amplification and restriction of the URA5 gene revealed that all 3 yeast isolates belonged to serotype A (C. neoformans var. grubii) and genotype VNII. This study adds new information on the ecology and molecular characterization of this yeast in Jos, Plateau State, Nigeria, where little is still known about the environmental diffusion of the serotypes and molecular types of the C. neoformans species complex.