Lower incidence of genital warts after HPV vaccine

A study in Sweden has shown that the incidence of genital warts (condylomata) declined by 93% in girls who received the human papillomavirus (HPV) vaccine before age 14. The study was carried out by researchers at Karolinska Institute in Sweden and published in Journal of the National Cancer Institute.

The researchers looked at 124,000 girls and women who were vaccinated against HPV between 2006 and 2010. The data showed that vaccination effectiveness was 76% (95% CI, 73% to 79%) among those who received 3 doses of the vaccine with their first dose before age 20. Vaccine effectiveness was highest in girls vaccinated before age 14 (effectiveness 93%, 95% CI, 73% to 98%).

Notably, the researchers also discovered that girls and women with at least one university-educated parent were 15 times more likely to be vaccinated before age 20 than girls and women whose parents did not complete high school (relative risk ratio = 15.45, 95% CI, 14.65 to 16.30).

The lead author noted in a press release from Karolinska Institute that the study results supported administering the HPV vaccine at a young age. In Sweden, the vaccine is now being offered free of charge through the public schools to all girls age 10-12.