High Genetic Diversity of Histoplasma in the Amazon Basin, 2006-2017

Histoplasmosis is one of the most common pulmonary mycosis diseases in the world. Genome sequencing has revealed that Histoplasma, the cause of histoplasmosis, is composed of several phylogenetic species. The genetic diversity of the pathogen remains largely unknown, especially in the tropics. We sequenced the genomes of 91 Histoplasma isolates from the Amazon basin of South America and used phylogenomics and population genetic evidence to measure the genetic variation of the genus in South America. We report a previously unidentified clade of Histoplasma endemic to the Amazon basin. The lineage is widespread across the continent and contains 5 lineages that are sufficiently differentiated to be considered phylogenetic species. We found the geographic range of those lineages is largely but not completely overlapping. Finally, we found that the patient median age and sex ratio differs among species, suggesting differences in the epidemiology of histoplasmosis caused by each Histoplasma lineage.