Human papillomavirus (HPV) vaccines, which prevent infection with HPV genotypes that cause cervical, anal, vaginal, and penile cancers, are hardly new. The quadrivalent and bivalent HPV vaccines were reviewed in AFP in 2007 and 2010, respectively, and a 9-valent vaccine was approved by the U.S. Food and Drug Administration in 2014. Although long-term studies have yet to demonstrate that HPV vaccines reduce cancer rates, a recent systematic review found that introduction of the quadrivalent vaccine in 9 countries (including the U.S.) was associated with a 90% reduction in infections from the targeted genotypes and similar reductions in genital warts and high-grade cervical abnormalities. Women who receive HPV vaccine are at considerably lower risk for undergoing colposcopy and associated invasive diagnostic or therapeutic procedures.
The Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices (ACIP) recommends that all boys and girls receive the 3-dose HPV vaccine series at age 11 to 12. However, CDC data from 2014 show that only 40% of girls and 21% of boys had completed the series by age 17. In contrast, 80% of 13 to 17 year-olds had received meningococcal vaccine, and 88% had received TdaP (tetanus, diphtheria, and acellular pertussis) vaccine, which provide protection against serious, but comparably rare, infections. Earlier this year, all 69 National Cancer Institute-designated Cancer Centers released a consensus statement expressing concern about persistently low HPV vaccination rates in the U.S. compared to other countries, which they labeled a "serious public health threat."
A 2015 AFP editorial by Drs. Herbert Muncie, Jr. and Alan Lebato examined parental and physician impediments to HPV vaccination. Parents often express concerns about vaccine safety and worry that their children may be more likely to start having sex after receiving the vaccine. Family physicians can reassure parents on both of these questions:
Parental safety concerns about the HPV vaccine increased from 4.5% in 2008 to 16% in 2010, although the reported adverse effects have been minor (e.g., injection site reactions, syncope, dizziness, nausea, headache). Studies have shown that adolescents who receive the HPV vaccine do not initiate sexual activity earlier, nor is their risk of acquiring an STI increased.
In other cases, physicians have been the primary obstacles to vaccination: they are sometimes reluctant to bring up the topic of sex, they believe the vaccine is unnecessary because Pap smears will detect early cervical cancer, or they present the vaccine as "optional" or don't offer it at all. Drs. Muncie and Lebato suggested several effective strategies for improving HPV vaccination rates:
Instead of discussing the vaccine as a means of STI prevention, physicians can present it as a way to prevent cervical cancer in women and oropharyngeal cancer in men. They can mention that immunologic response is greater in younger adolescents, so earlier immunization is prudent. Physicians should encourage HPV vaccine administration at the same time that other adolescent vaccines are given. They should review immunization status at every visit, and administer the HPV vaccine at any time—including during sick visits.
An editorial in AFP's July 15th issue by Drs. Jamie Loehr and Margot Savoy provided additional tips for physicians on addressing and overcoming vaccine hesitancy in general. More immunization resources, including the latest childhood and adult immunization schedules from the ACIP, are available in AFP's Immunizations Topic Collection.