Human papillomavirus (HPV) is the most common STD in the United States and certain strains of the virus can cause cervical cancer in women or oropharyngeal cancer in men. HPV also is associated with cancers of the vagina, penis, and anus, and all cases of genital warts and recurrent respiratory papillomatosis (warts growing in the throat). According to CDC researchers, recently published study results indicated that HPV prevalence in the United States declined by half in adolescent girls although only one-third of girls in the 13–17 age group had received the complete vaccine. The decline was much greater than health officials expected. In 2006, CDC’s Advisory Committee on Immunization Practices recommended the vaccine for girls ages 11 and 12 and a catch-up version for adolescents and women ages 13–26. In 2011, they recommended the vaccine for boys ages 11 and 12.
In the study, researchers compared HPV prevalence in American women ages 14–59 in the three-year periods before the vaccine (2003–2006) and after the vaccine’s introduction (2007–2010), using data from the National Health and Nutrition Examination Survey. More than 8,000 women participated by answering survey questions and providing vaginal swabs for CDC analysis. Results showed that HPV prevalence dropped 56 percent in girls ages 14–19, from 11.5 percent in 2003–2006 to 5.1 percent in 2007–2010. The drop in prevalence was 88 percent for girls who had received the vaccine. Researchers observed no decreases in other non-vaccinated age groups. These results were in spite of the fact that most young women were not getting the vaccine. CDC researchers reported that only 49 percent of 13–17-year-olds had received at least one dose and only 32 percent all three doses.
The full report, “Reduction in Human Papillomavirus (HPV) Prevalence Among Young Women Following HPV Vaccine Introduction in the United States, National Health and Nutrition Examination Surveys, 2003–2010” was published online in the Journal of Infectious Diseases (2013; doi: 10.1093/infdis/jit192).