Human papillomavirus (HPV) is the most common sexually transmitted infection (STI) in the United States, infecting millions of individuals each year. Moreover, thousands of people die each year from cervical cancer caused by HPV. But HPV is entirely preventable. With all that’s at stake, you’d think that parents would be tripping over themselves to get their daughters to the pediatrician’s office for the HPV vaccine as soon as possible. Unfortunately, that’s not what we’ve seen in the six years since HPV vaccines were released. Instead, parents have seemed reluctant to start the series and unmotivated to finish it.
Approximately 79 million Americans are currently infected with HPV. About 14 million people become newly infected each year. HPV is so common that nearly all sexually-active men and women will get at least one type of HPV at some point in their lives. Most people who have HPV will have no symptoms or health problems and may never even know they have it. Some people will get genital warts, which may go away on their own or may need to be removed by a health-care provider. However, certain strains of the virus, if left untreated, can lead to cervical cancer. Approximately 12,000 women in the United States are diagnosed with cervical cancer each year, and about 4,000 die. HPV can also cause cancer of the penis and anus, and is responsible for a recent increase in cases of head and neck cancers.
HPV is easily spread from infected skin to uninfected skin. Transmission of HPV can be prevented by condoms, but only if the infected skin is in an area covered by the condom. If it is on an area such as a man’s scrotum, condoms cannot help reduce transmission.
The good news is that HPV is one of the few STIs for which there is a vaccine. Actually, there are two: Gardasil and Cervarix. Gardasil was approved by the Food and Drug Administration (FDA) in 2007 and has been proven to protect women from four strains of HPV, including two that account for 70 percent of cervical cancers and two that account for 90 percent of genital warts. Cervarix was approved in 2009 and also protects against the two strains that cause most cervical cancers.
The vaccine is given as a series of three shots and is approved for young people—both men and women—between the ages of nine and 26. In order to ensure that it works, health-care professionals prefer to administer all three shots before a young person becomes sexually active, which is why the Centers for Disease Control and Prevention (CDC) recommends that HPV vaccines become part of the routine vaccinations for girls who are 11 or 12 years old.
HPV vaccines are considered a huge breakthrough for public health. They represent the first vaccines that can prevent cancer. (I always feel like I have to say that twice, and loudly: They prevent cancer!) The National Cancer Institute notes that if all women were to get the vaccines, the benefits would be long-term: “Widespread vaccination has the potential to reduce cervical cancer deaths around the world by as much as two-thirds.” Widespread vaccination would also reduce the health-care costs, physical costs, and anxieties that are associated with abnormal Pap test results. (A Pap test screens for cervical cancer and can detect precancerous changes to the cervix.)
Many Parents Do Not Vaccinate Their Children
So then why aren’t parents jumping on the HPV vaccine bandwagon? A new study in the April issue of Pediatrics aims to answer that question; it also looks at two other new vaccines suggested for adolescents. The study compares the parents’ responses to determine if they think about HPV differently because of its relationship to sexual activity.
Researchers used data from the federal government’s 2008-2010 National Immunization Survey of Teens to determine the percentage of teens who were and were not up-to-date on three vaccinations: HPV, Tdap/Td (which protects against tetanus, diphtheria, and pertussis), and MCV4 (which protects against a form of meningitis). Parents whose teens were not up-to-date on Tdap/Td and MCV4 were asked why they hadn’t vaccinated their child. When it came to HPV, the question was asked a little differently; parents were first asked if they planned to immunize their teen in the next year, and only those who said they did not plan to do so were asked why.
Overall, vaccination rates for teenagers between the ages of 13 and 17 are improving, though they remain below the 90 percent goal set by the government. The percent of teenagers who had received the Tdap/Td vaccine rose from 72 percent in 2008 to 81 percent in 2010. MCV4 rates rose from 42 percent in 2008 to 63 percent in 2010. HPV vaccine rates rose as well, but they remain significantly lower than for the other vaccines; just 19 percent of teen girls had been vaccinated in 2008 and 32 percent in 2011. Moreover, the percentage of parents who said they did not intend to vaccinate their daughters against HPV in the next 12 months actually grew, from 40 percent in 2008 to 44 percent in 2010.
It is important to note that while the numbers for the other two vaccines include both boys and girls, the numbers for the HPV vaccine only include girls who received all three shots. Though the CDC does recommend that boys receive the shots, in part to reduce overall HPV rates, it is often still thought of as a bigger issue for girls because only they can get cervical cancer. It is not yet known if vaccinating boys will protect them for the other types of cancers caused by HPV.
Reasons for Not Vaccinating
The most common reason parents cited for not vaccinating against Tdap/Td or MCV4 was that it was “not recommended” by their health-care provider. Parents also said they thought it was “not needed or not necessary,” admitted they had a “lack of knowledge” about the vaccine(s), or said they “didn’t know” why they had not vaccinated.
These were all also cited as reasons why parents didn’t vaccinate against HPV, but there were additional reasons as well. For instance, parents said they didn’t seek the vaccine because their child was “not sexually active,” their daughter was not the “appropriate age,” or they had “safety concerns/side effects.” While “lack of knowledge” was the primary reason cited in 2008 and 2009, in 2010 more parents (17 percent) said the vaccine was not necessary and 16 percent said they had safety concerns. In fact, the number of parents with safety concerns has increased dramatically, from 5 percent in 2008 to 16 percent in 2010.
The findings of this study suggest that while parents may think they have more knowledge about the HPV vaccines, there is still a great deal of misinformation out there.
Safety Concerns Unfounded
It is unclear where the increasing fears about the safety of HPV vaccines are coming from, though fears about vaccines in general have been on the rise over the past two decades. Much of this has been traced back to a report in the early 1990s linking some childhood vaccinations to autism. It turned out that this initial report (the results of which were never replicated) was completely fabricated by an unethical researcher with profit motives. Although this lie has now been made public, a general distrust in vaccines remains. A quick Google search will still pull up numerous anti-vaccine websites, many of which dedicate pages to the HPV vaccine. Still, these websites have been around for years, so it is hard to tell whether they are behind the disturbing results of this current study.
Regardless of what’s behind the safety fears, they are unfounded. Before any vaccine is put on the market, the FDA ensures that it is both safe and effective. Both Gardasil and Cervarix were carefully tested before getting FDA approval. Once on the market, the CDC tracks the safety of vaccines through three reporting systems: the Vaccine Adverse Event Reporting System (VAERS), the Vaccine Safety Datalink (VSD), and the Clinical Immunization Safety Assessment (CISA) network.
A 2009 report co-written by the CDC and the FDA combed through VAERS reports regarding Gardasil and found that 23 million doses had been administered in the United States between June 2006 and December 2008. In total, there had been 12,424 reports of adverse events following HPV vaccination. The vast majority of these cases (94 percent) were not serious and including fainting (which is common after needle shots, especially in teens and pre-teens), pain and redness at the site of the injection, dizziness, nausea, and headache. Though the more serious cases included blood clots, neurological symptoms, and death, the report was unable to find any evidence suggesting that the vaccine itself was the cause of these problems. In fact, in all of the cases of death, autopsies confirmed other causes. The report also concluded that although incidences of fainting and blood clots after Gardasil were higher than after other vaccines given to females of the same age, 90 percent of those who had blood clots had other “known risk factor for them, such as smoking, obesity or taking oral contraceptives (birth control pills).”
In 2011, the CDC looked at specific adverse events reported in the VSD following more than 600,000 doses of Gardasil, such as Guillain–Barré Syndrome (GBS), stroke, blood clots, appendicitis, seizures, fainting, allergic reactions, and anaphylaxis. No statistically significant increased risk for any of these adverse events was detected after vaccination.
Ultimately, the CDC concluded that “[c]linical trials and post-licensure monitoring data show that both vaccines are safe.”
HPV Vaccine Timing Is Misunderstood
The results also indicate that parents do not understand when their teens should be given the HPV vaccine. Over the three years of the survey, 11 to 14 percent of parents consistently suggested that they had not vaccinated their teen because she was not sexually active. Others felt their daughter was not the appropriate age for the vaccine.
It’s understandable that some parents would balk at the idea of preventing an STI in an 11-year-old. Though today’s tweens may look and sound a lot like teenagers, they are still very much kids and clearly not ready for sexual activity. This may make it seem like they are also not ready for the HPV vaccine, but just the opposite is true.
The CDC specifically recommends that young people be given the vaccine before they become sexually active so as they avoid exposure to HPV. If a teen waits until she has already had sex to get vaccinated, she may have already been exposed. Though the average age when individuals first have sex is around 17, some have sex earlier, and given that the vaccine is safe for individuals as young as nine, it makes sense to start it early. (The skeptic in me also has to wonder how many of the parents who think their teens aren’t sexually active are flat-out wrong.)
Though the aforementioned study did not conclude that parents fear the vaccine might encourage sexual activity, this has often been stated as a concern, and I wonder if it is consciously or unconsciously one of the reasons parents declare that their daughters are not the “appropriate age.” The good news is that research has found that access to the vaccine does not increase sexuality activity. One study reviewed medical records and found no differences between girls who got HPV vaccines and girls who did not when it came to pregnancy tests, STI diagnoses, or contraceptive counseling (all markers that would indicate sexual activity). Another followed girls between the ages of 15 and 24 and found that young women who are vaccinated against HPV are no more likely to be sexually active or to have more partners than un-vaccinated girls.
Even better, that same study found that girls who are vaccinated are “more likely to report always using a condom in the four weeks prior to the study than sexually active young women who had not received the vaccine.”
Changing Public Opinion
Over the past few years, public health professionals have concentrated on increasing the number of physicians who recommend the vaccine, as this had been one of the main reasons parents cited for not vaccinating. It seems as if these efforts have paid off, as fewer parents cited this issue in 2010. In fact, the percent of parents who did vaccinate their teen against HPV and who reported that their physician recommended it went from 40 percent in 2008 to 45 percent in 2009, dropping just a bit, to 44 percent, in 2010.
But the researchers suggest that physician recommendations may not be enough, and we need to explore other interventions. Merck, the company that makes Gardasil, launched an ad campaign called “One Less” when the vaccine went on the market, and it continues to build on that campaign today. The authors of the current study suggest that it might be time for state and federal agencies to develop social marketing campaigns to encourage the vaccine as well.