While known to help prevent anal and genital related cancers, the Human Papillomavirus vaccine may also provide protection against oral forms of cancer caused by HPV infections.

A new study by researchers at The University of Texas Medical Branch at Galveston found that those vaccinated had a lower prevalence of the HPV type that is responsible for some head and neck cancers.

The study findings were published in the journal Vaccine.

Proof that the vaccine protects directly against HPV–linked oral cancer is not yet available, as these cancers are rare and can take decades to develop.

“There is some evidence that HPV vaccination may protect against oral HPV infection but no current research has demonstrated this in the general population,” said Jacqueline Hirth, first author of the study and an assistant professor at UTMB.

HPV is responsible for the majority of oral and pharynx cancers in the U.S. and it is expected that HPV–related oral and pharynx cancer cases may exceed those of HPV related cervical cancer by 2020.

Hirth and other researchers at UTMB used data from the National Health and Nutrition Examination Survey between 2009 and 2014. Information from over 3,000 participants, 18 to 30 years old, who indicated whether they had received the HPV vaccine and had provided an oral sample, were included in the study.

“More research is needed on a larger sample of vaccinated and unvaccinated men and women because oral HPV infection is relatively rare,” Hirth said.

Other authors include Mihyun Chang, Vicente A. Resto, Fangjian Guo and Abbey B. Berenson, all of UTMB. This research was funded by the National Institutes of Health.