A single jab of the human papillomavirus (HPV) vaccine seems to work as well as the currently recommended two doses for adolescents, according to findings from a National Institutes of Health study in Costa Rica. HPV, a common sexually transmitted infection, triggers abnormal cell growth that can lead to cervical, genital, anal and oral cancer. The Gardasil 9 vaccine protects against nine high-risk HPV types. Ideally, young people should be vaccinated before they become sexually active.

If recommended by U.S. health officials later this year, a single shot, which is cheaper and less burdensome than a two-dose series, could boost uptake—and help eradicate cervical cancer.