Two recent pieces of news will change how we protect ourselves from the sexually transmitted human papilloma virus: The Food and Drug Administration has approved the use of the Gardasil vaccine in boys and men ages 9 to 26, and a new HPV vaccine, Cervarix, for girls and women ages 10 to 25. What this means is that HPV infections may drop precipitously, with both boys and girls getting vaccinated. It also means that girls and women will have a choice between two vaccines.
Concerning the first development, vaccine experts previously have told me that in order to make a dent in the vast number of women who become infected with HPV—about 80 percent at some point in their lives—men need to be vaccinated as well. While the government's Advisory Committee on Immunization Practices is expected to vote Wednesday to recommend routine vaccination for boys, what's not known is whether parents will get their sons vaccinated. Gardasil was approved to protect against genital warts, but these occur pretty rarely in men (only about 1 percent of the time), so they and parents of young boys may not feel the need for "altruistic" immunization just to prevent transmitting the infection to others. On the other hand, as my colleague Bernadine Healy pointed out in this column, HPV has been linked to a number of cancers that strike men, including anal, esophageal, and penile cancer.
With regard to Cervarix, I think it's intriguing that women now have a choice between two vaccines against HPV, each of which has different advantages. Both vaccines protect against two virus strains, HPV 16 and 18, which are responsible for about 75 percent of cervical cancers. And both are administered in three doses.
While some news reports predict that Gardasil will remain the vaccine of choice, I'm not so sure. With its three-year head start on the U.S. market, Gardasil is certainly better known to doctors and women. It also has the advantage of protecting against two HPV strains responsible for 90 percent of genital warts—which can cause itching and burning but not cancer. Cervarix, while it doesn't protect against these warts, offers some protection against another HPV strain. According to the manufacturer, GlaxoSmithKline, Cevarix is about 89 percent effective in preventing precancerous lesions caused by HPV type 31, the third most common cervical-cancer-causing strain, behind 16 and 18. It's a personal choice women will have to make on their own, although I'm guessing their decision may be influenced by multimillion dollar ad campaigns. Merck, manufacturer of Gardasil, already has ads on the airwaves, and I'm curious how Cervarix will be sold to women. Choose added cancer protection over freedom from warts?