Background Prisoners are a vulnerable population potentially at higher risk of sexually transmitted infections (STI), including bloodborne viruses (BBV), yet are more likely to receive fragmented sexual health services (SHS). Until recently, information on STI SHS provision and outcomes in this population has been limited in England.

Methods Following implementation of a new surveillance system, we assessed the quality of SHS received and outcomes among male prisoners seen by staff at 58 STI clinics during 2011 relative to other male attendees at all 209 clinics in England. Data on females were excluded due to small prisoner numbers. Significant differences were identified using chi-squared and t-tests. New STI diagnosis rates (DRs) were directly standardised using prisoners as the reference population.

Results Compared with other male STI clinic attendees (n = 627,976; 1,143,495 visits), prisoners (n = 3,216; 4,490 visits) were significantly younger (25 vs 28 years; p < 0.001), more likely to be of black ethnicity (13% vs 11%), UK-born (90% vs 80%) and heterosexual (97% vs 83%). Standardized new DRs for prisoners versus male attendees were higher for genital warts (5.5% vs 4.6%; p-value = 0.003), hepatitis B (0.4% vs 0.1%; p-value < 0.001) and hepatitis C (2.0% vs 0.0%; p-value < 0.001) but lower for genital herpes (0.3% vs 1.2%; p-value < 0.001), chlamydia (5.8% vs 9.3%; p-value < 0.001) and gonorrhoea (0.8% vs 1.6%; p-value = 0.008). New acute hepatitis A, syphilis and HIV DRs were similarly low (< 0.5%) for both groups. Comprehensive sexual health screens (48% vs 64%; p-value < 0.001) and HIV testing (68% vs 80%; p-value < 0.001) were offered less frequently to prisoners.

Conclusion We found high DRs of BBVs in prisoners, especially hepatitis C, but fewer diagnoses of bacterial STIs. As there were substantial missed STI testing opportunities in prisoners, however, bacterial STI DR estimates are likely understated. Efforts to improve opportunities for accessing STI and HIV testing services by prisoners should be a priority.