Despite repeated studies maintaining that HPV vaccines are safe, a growing number of parents believe the shots are unnecessary and continue to worry about reports of side effects, according to another new study. The results indicate that even though the vaccines, which are recommended by public health officials to thwart cervical cancer, drugmakers have much more work to do to convince a large swath of the population.
To wit, five years ago, 40 percent of parents surveyed said they would not vaccinate their girls against the human papillomarivus, which can lead to cervical cancer. In 2009, that rose to 41 percent and then climbed to 44 percent in 2010. And parents concerned about side effects rose from 5 percent in 2008 to 16 percent in 2010, according to the study, which was published in Pediatrics (here is the abstract).
"That's the opposite direction that rate should be going," Robert Jacobson, a pediatrician with the Mayo Clinic Children's Center and one of the study authors, says in a statement. For the record, he is on a safety review committee for a vaccine study and on a data and safety monitoring board for two other vaccine studies, all of which funded by Merck. The drugmaker markets the Gardasil HPV vaccine. GlaxoSmithKline sells Cervarix.
The study analyzed vaccination data for teens between the ages of 13 and 17 in the 2008-2010 National Immunization Survey of Teens. As of 2010, eight of 10 teens had the Tdap vaccine for tetanus, diptheria and pertussis, while about 63 percent had the MCV4 meningococcal vaccine. By contrast, only about one-third of girls had an HPV vaccine, although this was up was from 16 percent in 2008.
Just the same, a sizeable percentage of parents remain on edge when it comes to the HPV vaccines. Among the reasons cited: the vaccine was not recommended; there is a lack of knowledge; the vaccines are unnecessary; the vaccines are inappropriate for their child's age; parents worry about safety and side effects; and their child is not sexually active.
Although parents surveyed indicate that more physicians are recommending HPV vaccination, this occurs only about half of the time. "Pediatricians are letting it go in the early teens years and bringing it up only later. Then we're missing some teens because they tend not to see the doctor as frequently in the late teens as they do around 11, 12 and 13" years old, William Schaffner, a professor of preventive medicine at Vanderbilt University, tells MedPage Today. "Pediatricians really do need to continue to be vaccine advocates."
The findings underscore an ongoing challenge for public health officials and drugmakers. Ever since Gardasil was approved seven years ago, HPV vaccines have generated controversy. For one, Merck embarked on a surreptitious campaign to have Gardasil listed as a mandatory vaccine in schools, causing a backlash that forced the drugmaker to backpedal on its marketing (back story here and here). But as the study results indicate, convincing parents remains a big hurdle. In part, this reflects ongoing worries over vaccine safety, in general (see this). However, some parents and social conservatives continue to express concerns that HPV vaccines can be seen as a green light for teenage girls to engage in promiscuous sex, even though another recent study suggested that is not the case (back stories here, here and here).
Such concerns were underscored in yet another study last year that found nearly 24 percent of girls and women between the ages of 13 and 21 believed they were less at risk for getting a sexually transmitted disease after vaccination. That study, which was published the Archives of Pediatric & Adolescent Medicine, queried 339 girls and women about their views on sexual risks after their first HPV vaccination (read here).
For some, these concerns were likely reinforced during the Republican presidential primary campaign in fall 2011. At the time, Texas Governor Rick Perry was attacked by his rivals for the nomination for accepting Merck donations leading up to his controversial decision to unilaterally mandate Gardasil for school-age girls (see this).
Then, Congresswoman Michele Bachmann lambasted Perry for the contributions and the fact that his former chief of staff was by then a Merck lobbyist. She also told the NBC Today show that one mother approached after her a primary campaign debate to say her daughter was vaccinated and suffered “mental retardation.” Bachmann then said Gardasil can have “very dangerous side effects” (read here). The American Academy of Pediatrics quickly labeled this as false.
Gardasil, by the way, was initially approved for females between the ages of 9 to 26, and approval was expanded in 2009 to boys and men for preventing genital warts caused by certain types of HPV. GlaxoSmithKline’s Cervarix is approved for preventing HPV in females ages 9 through 25.
Despite the controversy, Merck (MRK) has finally managed to turn Gardasil into a big seller. Last year, the vaccine generated $1.6 billion in revenue, a 35 percent jump from the previous year and up 65 percent from 2010, the first full year in which Gardasil was marketed toward boys and men (see page 4). Glaxo (GSK), however, has not fared as well with Cervarix. Sales for its HPV vaccine declined 46 percent to about $408 million (see page 19).
The most recent study only illustrates that both drugmakers - and public health officials - will have to work harder to dispel concerns.
vaccine pic thx to lulu on flickr