As through a glass, darkly: the future of sexually transmissible infections among gay, bisexual and other men who have sex with men.

The trajectory of sexually transmissible infection (STI) incidence among gay and other men who have sex with men (MSM) suggests that incidence will likely remain high in the near future. STIs were hyperendemic globally among MSM in the decades preceding the HIV epidemic. Significant changes among MSM as a response to the HIV epidemic, caused STI incidence to decline, reaching historical nadirs in the mid-1990s. With the advent of antiretroviral treatment (ART), HIV-related mortality and morbidity declined significantly in that decade. Concurrently, STI incidence resurged among MSM and increased in scope and geographic magnitude. By 2000, bacterial STIs were universally resurgent among MSM, reaching or exceeding pre-HIV levels. While the evidence base necessary for assessing the burden STIs among MSM, both across time and across regions, continues to be lacking, recent progress has been made in this respect. Current epidemiology indicates a continuing and increasing trajectory of STI incidence among MSM. Yet increased reported case incidence of gonorrhoea is likely confounded by additional screening and identification of an existing burden of infection. Conversely, more MSM may be diagnosed and treated in the context of HIV care or as part of routine management of pre-exposure prophylaxis (PrEP), potentially reducing transmission. Optimistically, uptake of human papillomavirus (HPV) vaccination may lead to a near-elimination of genital warts and reductions in HPV-related cancers. Moreover, structural changes are occurring with respect to sexual minorities in social and civic life that may offer new opportunities, as well as exacerbate existing challenges, for STI prevention among MSM.