A British initiative to vaccinate teenage girls against the human papillomavirus (HPV) slashed cervical cancer rates by 87 percent when the vaccine was administered at age 12 and 13, 62 percent when offered at age 14 to 16, and 34 percent among women vaccinated at 16 to 18, researchers reported Thursday in the medical journal The Lancet. Cancer Research UK, which funded the study, called the results "historic" and said it proves the HPV vaccine saves lives.
Britain's National Health Service began offering the HPV vaccine to girls as young as 11 in 2008, and the new study compares cervical cancer outcomes between vaccinated and unvaccinated women now that the first cohort is in their 20s. Most cervical cancer is caused by one of two HPVs blocked by the vaccine, and immunization is much more effective if administered before teens become sexually active.
The Lancet study estimated that by June 2019, the vaccine had prevented 450 cases of cervical cancer in the immunized groups and 17,200 cases of precancerous cervical carcinomas. Cervical cancer is the No. 4 most common cancer in women worldwide and kills 300,000 each year, BBC News reports. Almost 90 percent of those deaths are in low- to middle-income countries, where the vaccine could have the biggest impact.
"We've known for many years that HPV vaccination is very effective in preventing particular strains of the virus, but to see the real-life impact of the vaccine has been truly rewarding," said lead author Peter Sasieni, of King's College London. "Assuming most people continue to get the HPV vaccine and go for screening, cervical cancer will become a rare disease."