Parents’ perceptions of the HPV vaccine: a key target for improving immunization rates

Keywords::

• attitudes
• health knowledge
• papillomavirus vaccines
• parents/px [psychology]
• patient acceptance of healthcare/px [psychology]
• practices
• vaccination/px [psychology]

The promise of the human papillomavirus vaccine

The USA has had a licensed vaccine directed against human papillomavirus (HPV) infections since 2006, and yet our most recent data from the year 2011 indicate only 35% of 13–17-year-old females have completed the three-dose series [1]. The two licensed vaccines (Gardasil®, HPV4, Merck & Co., and Cervarix®, HPV2, GlaxoSmithKline) demonstrate high rates of efficacy in preventing precancerous and cancerous changes in females [2,3], and post-licensure study has confirmed the safety of these HPV vaccines as determined by pre-licensure studies completed more than 10 years ago [4]. Parents' perceptions play a large role in impeding our progress with this vaccine’s uptake, and these perceptions of the HPV vaccine clearly differ from their perception of other vaccines. We will summarize what we know about the parental perceptions and consider how we should address these.

The problem of parental perceptions

In our recent study, we examined several aspects of HPV vaccination in the 2008–2010 National Immunization Survey of Teens [5]. From 2008–2010, parents reported that clinician’s recommendation for all adolescent vaccinations increased significantly; the highest rates of clinician recommendations were for HPV vaccination, and they increased from 47% to 52%. Over that same period, the reported rates of the parents’ intent to not vaccinate their adolescents against HPV increased from 40% to 44%. The reasons that the parents gave for intending to not vaccinate against HPV differed greatly from the other two adolescent vaccinations – the tetanus-diphtheria-acellular pertussis vaccine (Tdap) and the meningococcal conjugate vaccine (MCV). While <1% of the parents noted concerns for the safety and side effects with Tdap and MCV, 4.5% did with HPV in 2008 and that increased to 16% by 2010.

It is not just that the acceptance rate of HPV vaccination is poor; timely completion of the HPV vaccine series is also poor. In a study of the North Carolina immunization registry, of those of 138,823 females 9–26 years of age who had received at least one dose of HPV between 2006 and 2009, 55% completed the series and only 28% completed the series on time [6]. Based on data we have collected to evaluate hesitancy of receiving all adolescent vaccines, we have observed similar failures to receive the second and third doses of HPV within the recommended time. Of those who were up to date for HPV vaccine, we found that only half had received either their second or third doses on schedule. The perceptions may not only interfere with beginning the series but also with completing the series in a timely manner.

The reality regarding these perceptions

One of the most prevalent parental perceptions is that the HPV vaccine is not needed [5]. Variations on this theme are parents' beliefs that the vaccine is for others who are at increased risk, that the vaccine is not recommended for routine use, and their children will never be at risk. In reality, adolescents are at high risk. By 18–19 years of age, more than 60% of never-married adolescents in the USA have had sexual intercourse [7]. According to the Centers for Disease Control and Prevention (CDC), 14 million Americans acquire new HPV infections each year, and 79 million currently have the infection [101]. While 90% clear the infection in two years, about 21,000 individuals each year go on to develop cancers caused by HPV, including 12,000 females who develop cervical cancer.

A second major parental perception is that the HPV vaccine is harmful [5]. In fact, that perception increased from 4.5% to 16% from 2008 to 2010. Several safety concerns with the vaccine were raised upon licensure with its initial dissemination. These included syncope, Guillain-Barre Syndrome, and thromboembolic phenomenon. Syncopal reactions reported with the two HPV vaccines were first noted post-licensure, and the association determined to be causal but not specific to HPV vaccination [8]. The recognition of the increased risk led to specific recommendations to observe the HPV vaccine recipient for 15 min following vaccination [2,3]. In fact, the CDC has recommended in general that vaccinators monitor all adolescents for 15 min following any vaccination for syncope [9]. The concern that a vaccine can cause Guillain-Barre is not unique to HPV, and initial evaluations of the Vaccine Adverse Events Reporting System (VAERS) identified a possible association [10]. However, a post-licensure review by the US FDA and CDC and then by the Institute of Medicine (IOM) found no evidence of an increased risk of Guillain-Barre with HPV vaccine [11,12]. Similarly, early concerns for thromboembolic events following HPV vaccination were similarly studied and again found by the IOM to be coincidental and not causal [12]. A post-licensure study of nearly 200,000 female recipients of the vaccine found no association with chronic disease or persisting injury [4]. A similarly sized post-licensure study is underway in males (ClinicalTrials.gov Identifier: NCT01567813 [102]).

A third major parental perception is that the child is too young for the HPV vaccine because the child is not yet sexually active and will not be so for a long time [5]. To prevent HPV and its sequelae, one must complete the three-dose HPV vaccine series well before exposure. Still parents fear giving the HPV vaccine implicitly promotes sexual activity. Bednarczyk et al. conducted a retrospective cohort study in a large managed care organization examining exposure to HPV vaccine with the outcomes being visits related to pregnancy, sexually transmitted disease testing or contraceptive counseling. This found no clinically meaningful difference between the vaccine exposed group compared to the vaccine unexposed group [13]. Liddon et al. also examined this issue in a nationally representative survey and found no association between receipt of the HPV vaccine and being sexually active or having more sexual partners [14].

Addressing vaccine-hesitant parents

Surveys and qualitative research show that the degree of trust that the parent has in the clinician matters [15,16]. We are currently investigating approaches that would impact vaccine hesitancy in part through directly improving the trust that the parent and adolescent have in the person making the vaccine recommendation.

We teach an approach to make that communications more than an information transfer. Specifically, we use Alison Singer’s C.A.S.E. approach to vaccine hesitancy [17]. The clinician Corroborates the specific concern acknowledging for that individual asks an understanding of why that concern would be troubling, and perhaps identifying how others have had that concern. Then the clinician tells About oneself, establishing, how through study and experience the clinician has established his or her own expertise to address the concern. The clinician then summarizes the Science and links that summary to an impassioned effort to Explain the advice in terms of this particular patient.

We will also need efforts beyond the encounter-based communication. Reminder/recalls have been shown effective in improving vaccination rates in young children, and the use of text-messaging as a modern form of communication with adolescents has been shown effective with improved HPV vaccine-series completion rates [18]. Szilagyi et al. tested the use of a trained member of the community in a role similar to that of a case manager to improve the frequency of adolescent preventive visits and receipt of vaccinations [19]. Following two attempts with telephone and mail reminders, immunization navigators conducted home visits to remind patients to schedule preventive care including vaccinations. This intervention improved immunization delivery by 12–16%.

Brunson et al. examined the parents’ social networks and how they affect the parents’ vaccination decisions [20]. They examined parents who conformed to the recommended vaccination schedule and those who did not. They found the most important difference was the percentage of the people in their social networks who advised nonconformity with the schedule. Thus, efforts to change parental perceptions must really address the parents’ social networks and not just the parents themselves. Of note, however, healthcare providers ranked among the top five network members by both conformers and non-conformers. In fact, for both groups, the healthcare provider came second, only after the spouse, as the most highly ranked network member. Thus healthcare providers play an important role in this apparently important determinant of parental decision-making.

Conclusion

The first six years’ HPV vaccination rates indicate a much poorer uptake in teens than with the Tdap or MCV vaccination. Will we ever overcome negative parental perceptions and achieve comparable HPV vaccination rates? Negative perceptions concerning the Lyme disease vaccine (Lymerix®, GlaxoSmithKline) led to that manufacturer’s withdrawal of that safe and effective vaccine. We hold that directly addressing parental perceptions through both communications across the community as well as in office-encounters will be crucial to achieving high up-to-date HPV vaccination rates. We cannot afford to ignore these perceptions, and we cannot presume it will be easy to change them. Current approaches have failed to make sufficient progress; instead, we must invent, test, and deploy innovative strategies that more successfully address parental perceptions that impede HPV vaccination currently.

Financial & competing interests disclosure

R Jacobson is a member of the safety review committee for the Merck funded study of Gardasil (HPV4) in males, a member of the data monitoring committee for the Merck funded studies of pneumococcal vaccines in variety of age groups, and principal investigator on recently completed studies on pneumococcal vaccines with Pfizer and on meningococcal vaccines with Novartis. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.