Penile microbiome: decoding its impact on HIV risk.

Purpose of review: The penile microbiome has been linked to local inflammation and increased risk for sexually transmitted infections, including HIV. This review explores recent studies of this emerging area of HIV research.

Recent findings: The male urogenital tract supports multiple distinct niches, where their associated microbiome are shaped by abiotic (e.g., oxygen, moisture) and biotic (e.g., host immunity) environmental factors and host behaviors, particularly sexual activity. In addition, male circumcision is a significant drivers of male genital microbiome in both children and adults. Recent sexual partner studies provide new insight into the exchange of genital bacteria and concurrent local immune changes that may impact HIV risk.

Summary: The male genital microbiome is shaped by the local microenvironment and host behaviors including sexual activity. Improving our understanding of the connection between the male genital microbiome, local inflammation, and HIV susceptibility, as well as how pro-inflammatory genital bacteria are transmitted between sexual partners may inform new strategies to prevent HIV transmission.