(HealthDay News) — Human papillomavirus 16 (HPV16) infection seems to last a year or more longer in men >45 years of age than it does in younger men, according to new research published online January 9 in Cancer Prevention Research.

Christine Pierce Campbell, PhD, MPH, from the Moffitt Cancer Center in Tampa, Fla., and colleagues analyzed four years of samples from more than 1,626 men. The samples were collected every six months. During the study, 23 men had two or more positive oral HPV16 samples. Of these, 10 had HPV16 when the study began.

In the group that had HPV16 at the start of the study, nine had infections that lasted a year or more. Additionally, the researchers found that eight of these infections lasted two years or more, and two lasted four years or more, the researchers found. In those who developed infections during the study, the team found that infections in men >45 years of age all lasted one year or more. By contrast, just half the infections among men 31–44 years persisted for one year or longer. And none of the infections detected among men 18–31 years lasted for a year, according to the researchers.

“Our results show that some oral HPV16 infections persist in men for four years or more and that persistence seemed to increase with age,” Campbell said in an American Association for Cancer Research news release. “Oral HPV16 is the HPV type most commonly found in HPV-driven oropharyngeal cancers, which have been increasing in incidence recently in the United States,” she said. “We don’t know how long oral HPV infection must persist to increase risk for head and neck cancer, but we assume it would be similar to cervical infection, where it is generally believed that infections persisting beyond two years greatly increase the risk of developing cervical cancer.”

Full Text (subscription or payment may be required)