‘Certainly not in the heterosexual public eye’: Qualitative study of the contexts of syphilis transmission among heterosexually-identifying people in England

BackgroundRecent increases in syphilis diagnoses among heterosexual individuals are a growing public health concern. The NEXUS study aimed to qualitatively assess the contexts surrounding syphilis transmission among heterosexually-identifying individuals in England.MethodsWe conducted semi-structured interviews with heterosexually-identifying individuals diagnosed with primary, secondary, or early latent syphilis in the previous year, and with healthcare professionals (HCPs) involved in syphilis management. Participants were recruited from sexual health services across three regions in England between December 2023 and September 2024. A qualitative descriptive and interpretive approach was used. Transcripts were analysed using framework analysis, incorporating deductive and inductive coding. Service user and HCP data were triangulated to compare perspectives and enhance credibility.ResultsNineteen service users (53% male, 74% White British) and seven HCPs were interviewed. Syphilis was reported to occur in the context of condomless vaginal or oral sex. Many heterosexual individuals perceived low STI risk due to few partners, presumed exclusivity, or isolated changes in behaviour. Syphilis knowledge was limited and the infection was often viewed as rare or historical. Symptom recognition was poor, particularly for non-genital symptoms, and some service users initially sought care in non-sexual health settings, contributing to delayed diagnosis. HCPs highlighted similar gaps in awareness among non-sexual health clinicians. Following diagnosis, awareness of STI risk increased and most service users described intentions to reduce risk, although understanding of infectiousness and follow-up remained variable.ConclusionsFindings highlight gaps in awareness, risk perception, and clinical recognition of syphilis among heterosexual populations and non-sexual health HCPs. Public health strategies should emphasise syphilis as relevant to all sexually active people, raise awareness, and support earlier diagnosis by non-sexual health HCPs.