HPV vaccine may stimulate sensitive talk about STDs

Washington -- A vaccine that prevents infection from four strains of human papillomavirus, including the two that cause the majority of cervical cancers, is expected to be approved by the Food and Drug Administration this month.

In advance of the availability of Gardasil vaccine, physicians should begin thinking about the sensitive discussions that will likely take place with its target population -- preteen and young teen girls -- and with their parents.

This population will benefit most from the vaccine's protection, say public health experts. Specifically, 10- to 14-year-olds who are not yet sexually active are the group for which it would be most effective, said John Schiller, PhD, one of the vaccine's inventors and chief of the National Cancer Institute's Neoplastic Disease Section. Gardasil is unlikely to help with current infection, he noted.

Dr. Schiller spoke at a May 23 telephone briefing sponsored by the National Network for Immunization Information.

Many doctors caution that the recommendation for a vaccine to prevent a sexually-transmitted disease may come at a time when parents think their children are much too young to need it. However, since 32% of ninth-graders report already having had sexual intercourse, public health advocates are arguing otherwise.

Infection with HPV is common. Every year, about 6.2 million people in the nation become infected, primarily young women and men in their late teens and early 20s. Fortunately, most clear the virus from their systems before it causes great harm.

There is no treatment for HPV infection, although there are therapies for the health problems it causes -- genital warts, cervical cell changes and cervical cancer, according to the Centers for Disease Control and Prevention. Still, 3,700 women in the United States are likely to die from cervical cancer this year, according to the American Cancer Society.

The figures are frightening and studies show that many parents, interested in protecting their children, are likely to accept the vaccine. Five studies showed that 67% to 83% of parents were willing to have their daughters vaccinated, said Jessica Kahn, MD, MPH, an associate professor of pediatrics at the University of Cincinnati College of Medicine. Dr. Kahn also spoke at the briefing.

Parents' decisions were influenced by the vaccine's safety, their physician's advice and their own experience with HPV, said Dr. Kahn.

Benefits and a warning

Despite the vaccine's effectiveness, screening for HPV via Pap smears will still be necessary, at least for the near future, said Kevin A. Ault, MD, an associate professor of gynecology and obstetrics at Emory University School of Medicine in Atlanta. Although the new vaccine has been shown to be 100% effective in preventing infection with strains 16 and 18, the main cervical cancer culprits, "there are still the 30% of viruses that won't be covered by the vaccine," he said. There are more than 100 different HPV strains.

The vaccine is also 99% effective in preventing infection with strains 6 and 11, which cause genital warts.

On a negative note, Dr. Ault advised that women who are pregnant should not get the vaccine. There were five congenital anomalies reported by manufacturer Merck & Co., among women who conceived within 30 days of receiving the vaccine during trials. Pregnant women shouldn't "be the first on your block to get the vaccine," Dr. Ault said.

The approval of an HPV vaccine could spark more interest in instituting a "well teen" physician visit for preventive care. This is a concept long-supported by many health organizations, including the American Medical Association. Having left the days of childhood vaccines long behind, healthy adolescents previously had few remaining ties to preventive care.

However, this circumstance has changed in recent years. A shot that boosts immunity to pertussis is recommended for teens and a vaccine for meningococcal disease was approved recently and recommended for children ages 11 and 12, those entering high school and college freshmen living in dorms. Teens may also be playing catch-up with the hepatitis B series or a varicella shot. The CDC's Advisory Committee on Immunization Practices recently recommended that all children receive a hepatitis A vaccine and now, HPV is poised to arrive on the scene.

"Development and licensure of these vaccines may root a visit even more strongly," said William Schaffner, MD, professor and chair of the Dept. of Preventive Medicine at Vanderbilt University School of Medicine in Nashville, Tenn., and a fan of such visits.