The incidence of abnormal growths that can lead to cervical cancer fell by more than half among teenage girls in New Mexico from 2007 to 2014, a new study found.
The University of New Mexico study provides strong evidence for the effectiveness of vaccines that target the human papilloma virus, or HPV, that causes most cervical cancers, the study’s lead author said.
“If you take everything combined, the vaccines are better than we ever could have imagined,” said Dr. Cosette Wheeler, a researcher at the UNM Comprehensive Cancer Center.
The steep declines suggest that the vaccine offers “herd immunity” by lowering the amount of virus in the population, offering protection to women who have not received the vaccination, Wheeler said.
The study found that the rate of moderate precancerous lesions declined by 54 percent among girls 15 to 19 in the seven years after the HPV vaccine was introduced in 2007. It also found a 39 percent decline in moderate precancers among New Mexico women ages 20 to 24.
The study was published Thursday in the journal JAMA Oncology. It looked at cervical screening and treatment data for more than 220,000 New Mexico females under 30 from 2007 to 2014.
The results predict steep declines in cervical disease as vaccinated girls and women mature, particularly if HPV vaccination rates continues to increase, Wheeler said.
“If we do a good job of vaccinating, we have a chance in the next 20 years of actually eliminating cervical cancer,” she said.
Nearly 12,000 U.S. women were diagnosed with cervical cancer and 4,217 women died from the illness in 2013, the most recent year the data is available.
The study also suggests that researchers should consider scaling back cervical cancer screenings, which cost the U.S. health care system up to $8 billion a year.
Current guidelines call for women to get cervical cancer screenings every three years from ages 21 to 65. The protections offered by HPV vaccinations could allow the U.S. to safely delay of screenings to age 25 or later and reduce their frequency “to a few times in a lifetime,” providing huge savings and smaller risk of unnecessary treatments, Wheeler said.
“We are trying to not just remove disease, but save health care dollars,” she said. “The goal is to remove the disease and modify the way we spend money screening, because we don’t need to screen as early or as often.”
The 54 percent decline in cervical precancers among teenage girls was greater than researchers had expected. “The message is, 50 percent is way more than we anticipated,” Wheeler said.
Researchers had expected smaller declines, because public health officials have had only modest success in persuading parents to vaccinate their children for the sexually transmitted virus.
In 2014, 40 percent of New Mexico girls ages 13 to 17 had received the recommended three doses of HPV vaccine, up from 17 percent in 2008. The three-dose vaccine is recommended for boys and girls ages 11 and 12. HPV is a common sexually transmitted virus that infects about 80 million males and females in the U.S.
The vaccine guards against four common strains of HPV, including two strains that cause at least 70 percent of cervical cancers.
The study also bolsters the findings of earlier studies that the vaccine offers protection to women who received only one or two doses of the vaccine, she said.