As of late 2007, just one in five American girls under the age of 18 had received shots for human papillomavirus, or HPV, a treatment that can also protect against cervical cancer, according to the Centers for Disease Control and Prevention.
Experts say there are several reasons behind the low numbers, from parents who doubt that their child is sexually active to a mistrust of vaccines.
The
CDC recommends the shot for girls ages 11 to 12, in the hopes that they receive the vaccine before becoming sexually active. The
Food and Drug Administration recommended it for 9-year-olds, since the antibody response to the vaccine is better at younger ages than in the older girls.
Dr. Neal Halsey, a pediatrician and a professor at the Johns Hopkins Bloomberg School of Public Health, says that almost a decade ago, experts looked at age 11 as a good time for children to receive booster shots.
"It made more sense to establish a routine visit for adolescents," Halsey said. "And 11 to 12 years turns out to be an ideal time for doing a lot of other interventions with adolescents — education and evaluation."
Slow Vaccination Rates But Halsey, who is a member of advisory groups to the American Academy of Pediatrics and the CDC, says it's been slow going with most adolescent vaccines — unlike childhood immunizations, which 90 percent or more children have gotten by the age of 2.
Looking at adolescents, "even the routine booster doses of tetanus and diphtheria toxide were in the 50 to 60 percent range," Halsey said.
His expectations for the HPV vaccine have been tempered by experience. But the rate of HPV shots — especially for younger adolescent girls — is less than other vaccines.
Dr. Jessica Kahn says that she confronted that issue — as a pediatrician, a research scientist and a mother. She had her own doubts about giving the HPV vaccine to her daughter, Kahn said.
"When I brought her into her doctor's office, I said to the pediatrician, 'You know, she's 11. Maybe we should wait until she's 12 to get this vaccine,' " Kahn said.
"And so I really understand the concerns of parents who think, you know, 'My child really is not really at risk.' I thought, 'Oh, she's really not at risk — the vaccine is recommended for girls 11 to 12.'
"And my pediatrician said, 'Absolutely not; she's getting the vaccine.' "
Vaccines And Parental DoubtKahn says that in a survey of 10,000 mothers who were also nurses, less than half were opposed to giving an 11-year-old the vaccine, compared with 90 percent who would agree to it for 15- to 18-year-olds.
"Nurses might be expected to be more supportive of vaccination," Kahn said. "In a way, our study might overestimate the proportion of mothers who intend to vaccinate a 9- to 12-year-old daughter."
But, she says, middle- to high-income parents tend to be more suspicious of vaccines. And that's why communication between pediatricians and parents is important in easing concerns, Kahn said.
"If parents don't believe the vaccine is safe, and believe the vaccine has serious side effects, that will weigh against their daughter being vaccinated," Kahn said.
Since 2006, there have been 21 HPV-vaccine-related deaths reported to the CDC. The reports require no absolute proof of a link, only a suspicion of one. Researchers were able to investigate only 12 of the deaths.
At Johns Hopkins, Halsey says the evidence doesn't hold up. The rate of serious allergic reactions to the HPV vaccine, he said, appears to be about one in a million.
"To date, my knowledge of the investigations of those rare cases that have occurred have not led to any evidence to suggest that the vaccine was causally related to those," Halsey said.
"There has been quite a bit of coverage in the media related to adverse events caused by HPV vaccines," Kahn said. "And in my practice, I've noticed that that has impacted parents' willingness to vaccinate daughters."
The Consequences Of WaitingHalsey thinks that in time, as with most new vaccines, parents will eventually accept this one. But, he warns, there are consequences for putting it off.
"I do think there is a problem of waiting until you know your child is sexually active or you think they are, because then it may be too late," Halsey said.
The HPV vaccine provides no protection once girls are exposed to the strains that cause cervical cancer. That makes it vital that they get the shots before having a chance to contract HPV, health officials say.
"It is almost universal that children are sexually active — sometimes frequently — before the parents know they are sexually active," Halsey said. "So I wouldn't encourage parents to wait until they are suspicious that their child may be sexually active."
In Great Britain, a survey shows that up to 70 percent of parents would agree to have their young adolescent daughters get the vaccine against cervical cancer.
Part of the reason behind the difference may be that the shots are provided free of charge, through that country's national health service.
In the United States, cost is a major obstacle if the girl is not covered by insurance. The full course of vaccines costs about $400 in most cases.
Quick Facts: HPV VaccineThe HPV vaccine is recommended for 11- and 12-year-old girls.
It is also recommended for girls and women ages 13 through 26 who have not completed the vaccine series.
The vaccine can also be given to girls ages 9-10.
The vaccine is not recommended for pregnant women.
The retail price of the vaccine: about $125 per dose — three doses complete the treatment.
Treated women still need regular cervical cancer screening (Pap tests).
Source: Centers for Disease Control and Prevention