The prevalence of anogenital warts has decreased, with significant declines observed in specific populations such as women aged ≤39 years, men who have sex with women only (MSW) aged ≤39 years, and men who have sex with men (MSM) of all ages, according to findings published in Clinical Infectious Diseases. These declining numbers suggest that human papillomavirus (HPV)-associated morbidity is decreasing among patients who are treated at clinics for sexually transmitted diseases (STDs).
The significant majority (~90%) of genital warts are caused by HPV types 6 and 11, and the HPV vaccine has been recommended for select groups including girls and women, as well as gay, bisexual, and other MSM aged <26 years and men aged <21 years. In this study, researchers described age-specific trends in the annual prevalence of anogenital warts in patients who attended 27 STD clinics located in the United States between 2010 and 2016.
The overall prevalence of anogenital warts in women significantly declined from 2.3% in 2010 to 0.9% in 2016 (annual percentage change, −13.1%; 95% CI, −16.4% to −9.7%). The overall jurisdiction-adjusted prevalence of anogenital warts has also decreased significantly in all MSW during this period, from 7.3% to 4.4% (annual percentage change, −8.1%; 95% CI, −10.4% to −5.6%). The prevalence of anogenital warts in all MSM decreased significantly during 2010 to 2016, from 6.2% to 2.9% (annual percentage change, −11.3%; 95% CI, −13.1% to −9.4%); these declines were significant across age categories.
Although “it is likely that the observed decline in the proportion of patients attending STD clinics with [anogenital warts] is partially the result of US implementation of HPV vaccination,” the researchers noted that decreases in prevalence were also observed in age groups that are not targeted for vaccination and are “thus less likely to be affected, suggesting other factors may be impacting observed trends.”