Aussie stats show HPV shots effective, but will U.S. parents listen?

Could Australia's success with HPV vaccination help boost similar efforts in the U.S.? If hard numbers on results could help, then yes. A BMJ study shows that immunizing young women against the human papillomavirus has already proven its worth.

It's too early to tell whether the shots will cut cancer rates as well, because HPV-related cancers take decades to develop, the New York Times points out. But genital warts, another malady linked to HPV infection, can develop in a few months. And diagnoses of genital warts in young women and young men plummeted in the two years after Australia's vaccination program began. There was also a significant decline in the rate of cervical abnormalities, which can presage cancer.

Study author Basil Donovan, a professor at the University of New South Wales in Sydney, and his team looked at HPV-related diseases in the three years before Australia's vaccination program began and in the four years after, using data on 86,000 patients. Diagnoses of genital warts in girls and young women aged 12 to 26 dropped by 59% in those first two years, while diagnoses in boys and young men fell by 39%, showing that vaccinating females helped protect males, the researchers said. The rate of genital warts in girls under 21 fell to 1% from about 12% in 2007. Women 30 and older, who wouldn't have benefited from the vaccination program, showed no such decline.

"We were particularly surprised to see a 93 percent drop in genital warts in young women when only 85 percent were vaccinated," Donovan told the NYT. "This suggests that the herd immunity that is protecting men is, in turn, also protecting unvaccinated women."

These numbers would be music to the ears of Merck ($MRK) and GlaxoSmithKline ($GSK) executives. Their HPV-fighting shots Gardasil and Cervarix could use a boost, particularly in the U.S., where squeamish parents have put a damper on vaccination rates.

Australia's nationally funded HPV vaccination program didn't meet with much resistance, Donovan said. By contrast, only around one-third of U.S. girls and young women have opted for the shots--and that's despite recommendations from the Centers for Disease Control and Prevention, which backs the vaccinations for young women and young men. Many parents have chosen not to vaccinate their children, partly because HPV is sexually transmitted. Plus, some worry about reports of fainting spells and other side effects in girls who were vaccinated. Of course, government funding helped in Australia; in the U.S. some private insurers don't cover the three-dose course, which can cost around $300 out of pocket.

- see the NYT story