HPV Vaccine Added to Adult Immunization Schedule
The CDC’s Advisory Committee on Immunization Practices has updated its 2010 Recommended Adult Immunization Schedule to include either of the FDA-approved human papillomavirus (HPV) vaccines for women ages 19 to 26 who have not been immunized previously against HPV. The updated recommendations appeared January 5 in the Annals of Internal Medicine.
As of October 2009, the FDA had approved two different vaccines to prevent infections from two strains of HPV associated with more than 70 percent of cervical cancers. The vaccine Cervarix protects against HPV-16 and HPV-18, the two most common cancer-causing strains of the virus. The second vaccine, Gardasil, protects against HPV-16 and HPV-18 and against two strains of HPV that cause genital warts.
According to the schedule, either HPV vaccine would optimally be given to girls between the ages of 11 and 12, but women up to age 26 may benefit from “catch-up” vaccination. Both HPV vaccines are most effective when given before a woman becomes sexually active.
In addition, for the first time the CDC included a permissive recommendation that young males ages 9 to 26 may receive Gardasil for the prevention of genital warts, although questions remain “about whether vaccinating men will aid the development of herd immunity to reduce the societal burden of HPV-associated disease,” explained Drs. Robert H. Hopkins, Jr., and Keyur S. Vyas of the University of Arkansas for Medical Sciences in an accompanying editorial. Herd immunity results when enough members of a population are vaccinated to provide protection to unvaccinated members because a disease will have few opportunities to spread.
No studies comparing the effectiveness of Gardasil and Cervarix head-to-head have been published to date.