The primary barrier to increasing uptake of the human papillomavirus (HPV) vaccine is concerns about safety, especially among parents and caregivers.

A new study led by University of Texas School of Public Health researchers questions, however, whether that sentiment is in line with post-marketing vaccine safety surveillance data. To determine that, researchers performed a parallel assessment of trends in HPV-vaccine safety concerns and HPV-vaccine adverse event (AE) reporting.

The study, published in JAMA Network Open, was a cross-sectional analysis of the National Immunization Survey (NIS) and Vaccine Adverse Event Reporting System (VAERS). The focus was on trends in HPV-vaccine safety concerns and AE reporting for HPV vaccination from 2015 to 2018.

In the NIS, caregivers of 39,364 unvaccinated adolescents with a mean (SD) age of 15.57 (0.08) years—mostly white, 62.9%; male, 56.1%; privately insured, 62.6%; and above the poverty level, 79.3%—reported their reasons for not beginning the HPV vaccine series for their teen.

The authors note that safety concerns were cited as the primary reason for not initiating the HPV vaccine series and that those concerns increased from 13.0% (95% CI, 12.1%-14.0%) in 2015 to 23.4% (95% CI, 21.8%-25.0%) in 2018 (P for trend <.001). That equates to a change from 170,046 to 259,157 U.S. adolescents not initiating the vaccine because of safety concerns, according to the report.

The study also points out that the percentage of parents listing safety concerns as the main reason for HPV vaccine hesitancy increased in 30 states, with the largest increases—more than 200%—occurring in California, Hawaii, South Dakota, and Mississippi.

In terms of VAERS, 16, 621 AE reports following HPV vaccination were reported from 2015 to 2018. "The AE reporting rate per 100,000 doses distributed decreased from 44.7 in 2015 to 29.4 in 2018 (P for trend <.001)," the researchers point out. "The serious AE reporting rate, including those leading to hospitalizations, disability, life-threatening condition, or death did not change."

The study team emphasizes that the increased citing of safety concerns was contrary to AE reporting trends, adding, "These findings suggest an urgent need to combat the rising sentiment of safety concerns among caregivers to increase HPV vaccine confidence."

The article notes that the HPV vaccine is effective for the prevention of up to six cancers—cervical, anal, oropharyngeal, penile, vaginal, and vulvar. Yet, despite being licensed for more than a decade, "the HPV vaccine coverage remains suboptimal in the US, with 46% of vaccine-eligible adolescents not up-to-date in 2019. Furthermore, the coverage varied substantially across states (from nearly 80% in Rhode Island to only 30% in Mississippi). The coverage among U.S. adults aged 18 to 26 years was also low (only 21.5% in 2018)."

Another recent study, based on a model, predicts that the HPV vaccine will yield significant reductions in rates of throat and back-of-mouth cancers, but that it could take about 25 years to clearly see the results.

Johns Hopkins Bloomberg School of Public Health researchers analyzed national databases on oropharyngeal cancer cases and HPV vaccinations and projected the impact of HPV vaccination on the rates of these cancers in different age groups.

The study team estimates that the oropharyngeal cancer rate would decrease almost by one-half between 2018 and 2045 among people ages 36 to 45 years. On the other hand, the rate in the overall population would not vary much from 2018 to 2045 because older people, in whom most of those cancers occur, would still have rising rates.

The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.

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