Epidemiology and molecular characterization of Cryptococcus neoformans isolated from pigeon excreta in Mazandaran province, northern Iran

Summary Objective The aims of this study were to verify the presence of Cryptococcus neoformans in pigeon excreta in Mazandaran province, Iran, to identify the varieties of the C. neoformans isolates using D1/D2 and IGS sequencing, and determining the presence of the two mating types: α and a. Materials and methods Four hundred pigeon droppings samples were collected from 15 different cities in Mazandaran province over a period of 1 year (February 2010–March 2011). Identification of C. neoformans was determined based on growing brown colonies on Niger seed agar (NSA) and biochemical characteristics. We used MATα and MATa specific primers for determining mating type and sequence analysis of the D1/D2 and intergenic spacer regions were done. Results Out of 400 samples, 20 samples (5%) were positive for C. neoformans and all of these isolates were α mating types. Sequence analysis of polymerase chain reaction (PCR) amplicons of D1/D2 regions revealed that all of the isolates were C. neoformans var. grubii except two isolates that were C. neoformans var. neoformans . Conclusion Our results reinforced that the pigeon excreta is a favorable environment rich in nitrogen and supports the growth of C.  neoformans and the pigeon could play an important role in spread of this organism.