Just One HPV Vaccination Offers Significant Cancer Protection

New cancer prevention research published by researchers at The University of Texas Medical Branch (UTMB) at Galveston indicates that just 1-dose of a human papillomavirus (HPV) vaccine is as effective as multiple vaccinations for preventing pre-invasive cervical disease.

And, this study’s findings support the use of any HPV vaccine in reducing the burden of this disease, which is a leading cause of cervical cancer.

To determine the effectiveness of other HPV vaccine dose schedules, Ana M. Rodriguez, M.D., MPH, of UTMB, and her colleagues, examined information on 133,082 females, aged between 9 to 26 years.

This new analysis published by the American Cancer Society Journal on February 10, 2020, found females ages 15 to 19 years, who had received one, two, or three doses of the quadrivalent HPV (4vHPV) vaccine had lower rates of pre-invasive cervical disease, cervical intraepithelial neoplasia II/III, than adolescents who were unvaccinated.

Within 5 years, 2.65 percent of unvaccinated teens aged 15 to 19 years developed the pre-invasive cervical disease, compared with 1.62 percent, 1.99 percent, and 1.86 percent in the one-, two- and three-dose groups, respectively. 

The risk of pre-invasive cervical disease was 36 percent, 28 percent, and 34 percent lower for adolescents who received one, two, and three doses, respectively, compared with adolescents who were unvaccinated.

For females less than 15 years old and those 20 years and older, the investigators did not find significant differences among the vaccinated groups in terms of risk for pre-invasive cervical disease.

"This study shows the impact of vaccinating at younger ages and its lasting long-term protection against cervical cancer," said Dr. Rodriguez, in a related press release.

"It is important to educate parents about the need to vaccinate their children."

HPV is the most common sexually transmitted infection in the USA, and persistent infection with certain types of the virus can cause cervical cancer.

About 14 million people, including teens, become infected with HPV each year.

To prevent infection, the Centers for Disease Control and Prevention (CDC) currently recommends both boys and girls under the age of 15 years receive a 2-dose schedule of the HPV vaccine, Gardasil 9.

The Gardasil 9 vaccine helps protect females ages 9 to 45 against cervical, vaginal, vulvar, and anal cancers and genital warts caused by 9 types of HPV. 

The vaccine has not been causally associated with adverse pregnancy outcomes or with adverse effects on the developing fetus, but data on vaccination during pregnancy are limited, says the CDC.

Gardasil 9 is indicated to help protect males ages 9 to 45 against anal, neck and throat cancers and genital warts caused by HPV infections.

All vaccines used in the USA, including HPV vaccines, are required to go through years of extensive safety testing before they are licensed by the U.S. Food and Drug Administration.

Study Author Contact: Christopher Smith Gonzalez, of The University of Texas communications office, at [email protected] or +1 409-772-8790.

HPV vaccine news published by Vax Before Cancer.