Epidemiology of human papillomavirus on anogenital warts in Portugal - The HERCOLES study.

Abstract

Anogenital warts (AGW) are one of the most prevalent sexually transmitted disease worldwide. Approximately, 90% of AGWs are related to infection by HPV 6 and 11. However, AGW have been associated with infection by multiple genotypes, including HR-HPV, which may be associated with a long-term increased risk of anogenital cancer. This observational prospective epidemiological study aims to estimate the type-specific HPV distribution on incident AGWs in both genders, and additionally to assess the frequency of anal and oral HPV infection in patients with AGWs. According to defined inclusion criteria, individuals with incident clinical diagnosis of AGWs were recruited in seven Portuguese Centres. HPV genotyping was performed using CLART HPV2 test. Between November 2012 and March 2014, 162 women and 400 men (mean age: 34 years), were enrolled. After exclusion of patients with unqualified AGW samples, HPV was detected in 95.3% (505/530) AGW patients, 96.8% males and 91.6% females. Among men who have sex with men, HPV was detected in 98.5% patients. HPV 6 and/or HPV 11 were the most frequent genotypes (87.5%), and HPV 16 the most common HR-HPV (9.2%). Infection with HPV 6/11 and any HR-HPV was observed in 35.8% patients. HPV prevalence on the anal canal and oral mucosa was 83.1% and 15.0%, respectively. Incident AGWs were more frequent in males than in females. LR-HPVs were more common among males and HR-HPVs among females. HPV 6 and 11 were the most common genotypes on both genders. However, there was also a high prevalence of HR-HPVs, particularly of HPV 16. AGWs represent a clinical marker of both anal and oral HPV infections, including anal HR-HPV infections in women and men who have sex with men. The HERCOLES study could be a clue to further investigations concerning HPV burden of disease by gender and sexual behaviour.