Cervical Precancers Drop Since Introduction of HPV Vaccine

A study using data from the Centers for Disease Control and Prevention (CDC) provides evidence that the human papillomavirus (HPV) vaccine is effectively reducing the numbers of cervical precancers – lesions that can become cervical cancers. The study was published February 21, 2019 in Cancer Epidemiology, Biomarkers, & Prevention.

Cervical cancer is the most common cancer linked to HPV in women. Nearly all cervical cancers are caused by HPV, and most of them are caused by types 16 and 18. The HPV vaccine can help protect people from the types of HPV infections that can cause cervical cancer as well as cancers of the vulva, vagina, penis, anus, and mouth and throat.

This study focused on a time period that began 2 years after the first HPV vaccine was introduced and ended a year before the newer, current vaccine was approved. The first vaccine protected against HPV types 16 and 18. The vaccine now used in the US helps protect against 9 types of HPV, including 16 and 18. The study included women who had been vaccinated and those who had not and found that cervical precancers caused by HPV types 16 and 18 have declined.  

The researchers tested tissue samples collected between 2008 and 2014 from more than 10,000 women ages 18 to 39 years who were diagnosed with cervical precancers. They found:

• The percentage of precancers caused by HPV types 16 and 18 declined from 52.7% in 2008 to 44.1% in 2014.
• Among women who had been vaccinated, the percentage of precancers caused by HPV 16 and 18 dropped from 55.2% to 33.3%.
• In unvaccinated women, the percentage dropped from 51% to 47.3%.

The decline was biggest among women who had been vaccinated, but unvaccinated women also showed a decline. The study authors say this suggests herd protection, which happens when enough people in a community are vaccinated and it’s harder for the virus to travel from person to person.

HPV and HPV Vaccination

The American Cancer Society recommends that the HPV vaccine be given to boys and girls between the ages of 9 and 12. Children and young adults age 13 through 26 who have not been vaccinated, or who haven't gotten all their doses, should get the vaccine as soon as possible. Vaccination at the recommended ages will help prevent more cancers than vaccination at older ages.

Due to changing COVID-19 restrictions, decisions about restarting in-person visits depend on many factors and they may not be the same for every person. They will likely be different for each community while the pandemic continues, even for routine vaccinations. You should consult your doctor or a health care provider for guidance.