The first generation HPV vaccine cut cervical cancer rates among women by 87%, British researchers reported.
The study published Wednesday in the journal The Lancet 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.
Researchers at Kings College London and the British government looked at population-based cancer registry data in the UK between January 2006 and June 2019 for seven groups of women, comparing those who were vaccinated to those who were not.
They were looking at data covering the Cervarix vaccine, which protects against two strains of cancer-causing human papillomavirus or HPV. Newer vaccines sold under the Gardasil brand protect against even more strains of cancer causing viruses.
Of the three groups that were vaccinated, each were vaccinated at different ages. One group was vaccinated at age 12-13, another at 14-16, and another at 16 -18. Those vaccinated at the earliest ages were the most protected, the team reported. Those who got the shot between the ages of 14 and 16 saw an 62% reduced rate, and rates were reduced by 24% among those vaccinated between 16 and 18.
“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.
“This represents an important step forwards in cervical cancer prevention. We hope that these new results encourage uptake as the success of the vaccination program relies not only on the efficacy of the vaccine but also the proportion of the population vaccinated.”
Cervical cancer is rare among young women, so it is still too early to determine the full impact HPV immunizations have on overall cervical cancer rates. The UK also stopped using the HPV vaccine in this study in 2012. Now instead of the Cervarix vaccine, the UK uses the Gardasil vaccine instead.
Last year the World Health Organization launched the Global Strategy to Accelerate the Elimination of Cervical Cancer, the first-ever global commitment to eliminate cancer, setting a target of getting 90% of girls fully vaccinated against HPV by the time they turn 15.
In January, the US Department of Health and Human Services also launched a campaign to increase HPV vaccination rates. The campaign specifically targeted states with some of the lowest HPV vaccination rates, including South Carolina, Texas and Mississippi.
In 2021, the American Academy of Pediatrics found that the HPV vaccination rates are getting better, but fewer than half of young adults in the US have received one or more doses, and the HPV vaccination rate has not yet caught up to the rate of other vaccines. The CDC began recommending the HPV vaccine for girls 11-12 years old in 2006. A 2021 CDC report found that cervical cancer rates in the US have dropped significantly thanks to the HPV vaccine.
HPV is the most common sexually transmitted virus in the US. While it usually resolves on its own, persistent HPV infection puts women at an increased risk for cervical cancer, cancer in the back of the throat and anogenital cancer. HPV also puts men at an increased risk of anal, penile and throat cancer.