When is it a sexually transmitted infection? Intimate contact transmission of pathogens not traditionally defined as STIs.

Purpose of review: Several microorganisms, which are not traditionally considered sexually transmitted infections (STIs), are capable of sexual transmission and have the potential to cause global outbreaks. The aim of this review is to describe pathogens which are not traditionally defined as STIs, to grant insight on current and potential outbreaks and call for clinical vigilance among members of key populations.

Recent findings: Recent findings emphasize that several pathogens, not traditionally classified as STIs, can be sexually transmissible. These include the mpox virus, enteric infections such as Shigella spp., dermatophytes such as Trichophyton mentagrophytes, ectoparasites and atypical bacterial genito-urinary infections such as Neisseria meningitidis. The internationally reported outbreaks and the reports on potential sexual transmission of these pathogens underlines the emerging risks, the need for a broader STI definition and the importance of vigilant public health control strategies.

Summary: These findings suggest that clinical practice should broaden STI testing and awareness to include pathogens not traditionally considered sexually transmissible, particularly among key populations. Clinicians must be vigilant for atypical presentations, ensuring comprehensive sexual healthcare and diagnostic testing. Development of targeted preventive efforts and continuous surveillance to detect and manage emerging sexually transmissible infections is paramount.