Adult HPV vaccination has limited impact

The Costa Rica Vaccine Trial for human papillomavirus (HPV) in young women has had a “modest” impact on gynecologic outcomes in the first few years of the program. Data shows that the impact of vaccination on rates of cervical cytology screening, colposcopy, and treatment was greatest among women with no evidence of prior HPV exposure (“HPV-naïve”). The 4-year trial involved 7466 women aged 18–25 years who were randomly assigned to receive either HPV or hepatitis A vaccination (control). For this post-hoc analysis, Ana Rodriguez (INCIENSA Foundation, San José, Costa Rica) and colleagues focused on the 6844 women who were sexually active and provided cervical samples, of whom 2284 were HPV-naïve. Reporting their findings in the American Journal of Epidemiology, Rodriguez et al show that women who received the HPV vaccination were significantly less likely to have an abnormal cytologic diagnosis of high-grade squamous intraepithelial lesion during the 4-year trial than controls, at 6.5%...