In more excellent vaccine news, researchers say the first-generation HPV vaccine has cut cervical cancer rates among women by 87%.

The HPV vaccine has been available since 2006— the point where researchers from Kings College in London began their study, which concluded in 2019. They used population-based cancer registry data in the UK during that time frame to compare those who were vaccinated and those who were not.

The human papillomavirus (HPV) is the most common sexually transmitted infection, according to the U.S. Centers for Disease Control and Prevention. In 2018, there were 42.5 million new or existing HPV infections in the United States. Most people infected were in their late teens and early 20s.

The study focuses on data covering the Cervarix vaccine, which protects against two strains of cancer-causing HPV. Since 2006, newer vaccines sold under the Gardasil brand protect against even more strains of cancer-causing viruses.

Published in The Lancet, the study estimates that by mid-2019, there were 450 fewer cases of cervical cancer and 17,200 fewer cases of pre-cancers than expected in the vaccinated population.

Three groups of vaccinated participants were studied during the 13-year span of the research—ages 12-13, ages 14-16, and ages 16-18.

The younger the participants were vaccinated, the more protected they were by the vaccine.

Participants who were vaccinated between the ages of 14 and 16 saw a 62% reduced rate of cervical cancer, and those vaccinated between 16 and 18 saw a reduced rate of 24%.

As for pre-cancerous growth, women who were vaccinated between the ages of 12 and 13 saw a reduced rate of 97% than those in previous generations. In women vaccinated between 14 and 16, they were 75% lower, and in women vaccinated between 16 and 18, they were 39% lower, according to the study.

“This study provides the first direct evidence of the impact of the UK HPV vaccination campaign on cervical cancer incidence, showing a large reduction in cervical cancer rates in vaccinated cohorts,” study co-author Dr. Kate Soldan from the UK Health Security Agency said, per CNN.

The American Academy of Pediatrics recommends children as young as nine should get the HPV vaccine. The HPV vaccine works best when people are vaccinated before they become sexually active, though a person should still get the vaccine even if they are sexually active—it’s unlikely that they’ve been exposed to all the types of HPV contained in the vaccine.

The Gardasil vaccine is the only HPV vaccine currently distributed in the U.S., and it protects against nine types of HPV. More than 54% of American teens were fully vaccinated against HPV in 2019, according to CDC data.