This talk will review what is known about risk factors for oral HPV infection. Performing oral sex is the primary risk factor for oral HPV infection, but many people with oral HPV and HPV-related oropharyngeal cancer have modest number of oral sex partners. Oral HPV prevalence incidence is much lower than that for genital HPV, although oral sexual behavior is common. It has been noted for many years that men have a higher incidence of oral HPV infection and HPV-related oropharyngeal cancer than women, but reasons for this difference were not understood.
Recent data will be reviewed which help to explain these gender differences in oral HPV infection.
Differences in oral HPV infection are not explained by behavior (i.e. when you compare men and women who both perform oral sex – with a similar number of people – men are still more likely to acquire an incident oral HPV infection than women. The more oral sex partners a man has, the higher their risk of oral HPV infection. In contract, performing oral sex was not a risk factor for oral HPV infection in women. Instead, women with more vaginal sexual partners actually had a lower chance of getting an oral HPV infection.
This data is consistent with the hypothesis that women may mount a stronger immune response to genital HPV infection than men do, and when they do women may become protected from subsequent oral HPV infection. These data suggests higher rates of oral HPV infection in men are, at least in part, because they are less likely to have a strong natural immune response from prior genital HPV infection.