HIV-positive gay men in France have a very high prevalence of anal infection with strains of human papillomavirus (HPV) associated with a high risk of anal cancer, investigators report in the Journal of Infectious Diseases. HPV16 was the most commonly detected high-risk HPV (HR-HPV) strain.

Overall, 70% of participants had a high-risk anal HPV infection, with 29% having HPV16, the type of HPV most strongly associated with anal cancer.

“Anal HPV16 and HR-HPV infection was confirmed to be highly prevalent,” comment the authors. “HPV16, the most common anal HR-HPV type in this population, predominated over other HR-HPV types.”

Prevalence of HPV16 increased with the severity of pre-cancerous anal cell changes and lesions. Cell changes in the anus are classified as low-grade intraepithelial lesions, high-grade intraepithelial lesions or anal cancer. High-grade lesions are less likely to disappear without treatment and more likely to lead to the development of anal cancer (although anal cancer remains a relatively rare cancer).

Infection with HR-HPV accounts for 90% of all cases of anal cancer. Prevalence of anal HPV infection and incidence of anal cancer are higher among HIV-positive gay and other men who have sex with men (MSM).

However, information on the risk factors and disease course of anal HPV infection in HIV-positive MSM is scarce. The French ANRS EP57 APACHES study was therefore established to better characterise the prevalence and evolution of anal HPV infection and HPV-related lesions in HIV-positive MSM. As a first step, investigators examined baseline prevalence of HR-HPV, especially HPV16, and their risk factors.