Vaccine shown to reduce cancer-causing sex virus in teen girls
Vaccinating teen girls against human papillomavirus, the most common sexually transmitted infection, has helped lead to a 56 percent decline in cases among young women, a report has found.
Among females 14 to 19, the prevalence of certain strains of HPV dropped to about 5 percent in 2007-2010 from about 12 percent in 2003-2006, according to an article released yesterday in The Journal of Infectious Diseases. The shot is 82 percent effective against the virus that can cause cervical cancer if at least one of the three recommended doses is given.
The report suggests inoculation against HPV with vaccines such as Merck & Co.’s Gardasil, approved in 2006, may help achieve a goal of eliminating cervical cancer caused by the virus. The 56 percent drop in strains of HPV covered by the vaccine from 2003-2006 to 2007-2010 was greater than expected as 34 percent of females ages 14 to 19 report having received at least one dose of the vaccines, the report said.
“These are striking results and they should be a wake-up call that we need to increase vaccinations,” Thomas Frieden, director of the Centers for Disease Control and Prevention, said yesterday in a call with reporters. “It is possible to protect a generation from cancer and we have to do it.”
HPV is the main cause of cervical cancer, according to the CDC, and about 12,000 women get cervical cancer each year. The vaccine needs to be given before a person becomes sexually active to prevent cervical cancer in adults.
Merck’s Gardasil protects against four strains of the virus linked to genital warts and cervical cancer. The vaccine generated more than $1.6 billion in 2012 sales for Whitehouse Station, N.J.-based Merck, the company reported.
Cervarix is an HPV vaccine from London-based GlaxoSmithKline, which had about $428 million in 2012 sales, according to data compiled by Bloomberg. The Food and Drug Administration approved Cervarix in 2009.
The prevalence of the HPV strains covered by the vaccine decreased among females ages 14 to 19, and no decreases were observed in other age groups during the two time periods studied.
The HPV vaccine was introduced into the routine immunization schedule in late 2006 for 11- or 12-year-old girls, with catch-up vaccinations recommended for those 13 to 26. In 2010, three-dose vaccination coverage was 32 percent among those 13 to 17.
A total of 4,150 females in 2003-2006 and 4,253 females in 2007-2010 ages 14 to 59 were included in the analysis.