October 30, 2019
By Anne Harding
NEW YORK (Reuters Health) - Oral human papillomavirus (HPV) infection is significantly less frequent among sexually active female adolescents who have received the quadrivalent vaccine than among their unvaccinated peers, according to new research.
"This study provided real-world evidence of the potential benefits of vaccination in a population of sexually active adolescent women, which was reflected by the lower prevalence of HPV-vaccine types in the oral cavity among vaccinated compared to unvaccinated women," Dr. Nicolas Schlecht of Roswell Park Comprehensive Cancer Center in Buffalo, New York, told Reuters Health by phone.
The findings were published online October 25 in JAMA Network Open.
HPV detection in the oral cavity has been associated with an increased risk of a subset of head and neck cancers, while HPV detection in the cervix is associated with cervical cancers.
Dr. Schlecht and his colleagues collected oral-rinse samples from 1,259 sexually active female adolescents treated at the health center. Mean age at the beginning of the study was 18; and half of study participants were African American and 45% were Hispanic.
At baseline, 78 study participants (6.2%) tested positive for HPV DNA. Study participants who had sex for the first time at least four years previously were significantly less likely to be HPV-positive than those who had begun having sex within the past year (odds ratio, 0.45).
Vaccine HPV types (HPV-6, HPV-11, HPV-16, HPV-18) were significantly less likely to be detected in those who had received at least one dose of the quadrivalent vaccine (OR, 0.20).
HPV in the cervical sample collected at the time of the oral sample was the most consistent predictor of oral HPV infection.
Dr. Schlecht and his team are continuing to follow the study participants, and have launched a similar pilot study in male adolescents.
"This study does provide one more illustration of the ability we have to potentially protect or reduce HPV infection and associated cancers . . . through this widely available and safe vaccine," he said.
The findings provide "strong evidence that HPV vaccination is associated with fewer episodes of oral HPV detection. That implies that vaccinated adolescent girls and young women may gain protection against oral HPV infections and decrease their future risk of HPV-associated head and neck cancers," Dr. Rachel Katzenellenbogen of Indiana University School of Medicine in Indianapolis told Reuters Health by email.
"It will be important to determine rates of oral HPV in adolescent boys and young men, and also to identify if HPV vaccination in young males is associated with decreased oral HPV detection, like that of these female study participants," added Dr. Katzenellenbogen, who co-authored an editorial accompanying the study.
"For oral HPV infections in this young group, we need to determine the rates of HPV infection, persistence, and clearance in order to understand their future risk of HPV-associated head and neck cancers. We also need to understand the level of protection against oral HPV infections gained by vaccination," she said.
The study had no commercial funding. Dr. has been a paid advisor to Merck.
SOURCE: https://bit.ly/2WvZrAT and https://bit.ly/2WsvJwt
JAMA Netw Open 2019.
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