HPV in young people’s epidemiological research study

Method

We explored the incidence of anal, penile, and oral HPV infection and the chance of HPV spreading to a partner for teenage MSM. We collected a swab from the anal canal at baseline, 3, 6, and 12 months. Participants self-collected a swab from the penis and provided an oral rinse.

HPV infection was measured by the presence of HPV DNA in the anus, penis, or mouth at any time in the 12 months:

• A definite incident of HPV infection was defined if the same HPV type was detected more than once from the same site in men who had a negative HPV test at baseline
• A possible incident HPV infection was defined if there was only one positive test during the 12 month study period

Outcomes

Over the 12 months of follow-up, 48 definite cases and 107 possible HPV infections were found in the anus, ten definite and 34 possible on the penis, and no definite and 6 possible infections in the mouth.

The chance of HPV spreading from the penis to the anus was estimated at approximately 33% whereas from the anus to the penis varied from 1 - 14%. We also found that overall, 39% of men had at least 1 HPV type, 23% had a vaccine-preventable type (6, 11, 16 or 18).

This study demonstrated that early and high per partner transmission of HPV occurred between men soon after their first sexual experiences. HPV vaccination needs to begin early for greatest prevention of HPV among MSM.

Antibody responses

These swabs were also tested to determine antibody responses in teenage MSM following a new anogenital infection with HPV. We found the likelihood of any antibody responses following anogenital HPV infections depends on the HPV type and site of infection.

Knowledge and attitude to vaccination

We also surveyed this group on their knowledge and attitudes towards HPV vaccination. Overall, very young MSM expressed high acceptance of HPV vaccination. 

Sexual behaviours

The participants completed a questionnaire about their sexual behaviours. They were also tested for gonorrhoea, chlamydia, syphilis, and HIV.

The questionnaire explored:

• age at first sexual behaviour of each type, with both men and women
• detailed sexual behaviours implying risk for sexually transmissible infections (STIs) and HIV
• detection of STIs

We found that:

• the average age at first insertive or receptive anal sex was 17 years
• half of the men reported having sex with mainly older men. Men within this age group were more likely to engage in receptive anal sex than other men (48% vs. 25%)
• most men had engaged in insertive anal sex (87%) and receptive anal sex (85%) in the past 12 months
• condom use in the last 12 months reported as sometimes with insertive anal sex was 60% and receptive anal sex 53%
• pharyngeal gonorrhoea was detected in the throat of 3% of men, rectal gonorrhoea in 6%, urethral chlamydia in 3%, rectal chlamydia in 4% and syphilis in 2% of men
• all men were HIV-negative

Preventative messages and STI testing interventions that are age appropriate need to be developed to reduce HIV and STI risk in this under-recognised group.

Publications