Although vaccination rates against the human papillomavirus (HPV) remain low for young adults across the United States, the number of self-reported HPV vaccinations among women and men between the ages of 18 and 21 years has markedly increased since 2010, according to new research findings.
The findings were published online April 27 as a research letter in JAMA.
In 2006, the US Food and Drug Admistration approved the HPV vaccine for the prevention of cervical cancer and genital warts in female patients. Three years later, the FDA approved the vaccine for the prevention of anogenital cancer and warts in male patients.
The Advisory Committee on Immunization Practices and the Centers for Disease Control and Prevention recommend two doses of the HPV vaccine for children aged 11 to 12 years. Adolescents and young adults may need three doses over the course of 6 months if they start their vaccine series on or following their 15th birthday.
For persons who have not previously received the HPV vaccine or who did not receive adequate doses, the HPV vaccine is recommended through age 26. Data on the rates of vaccination among young adults between 18 and 21 years of age in the United States are sparse, and it is not known how well vaccination programs are progressing in the country.
In the recently published JAMA research letter, investigators from the University of Michigan, Ann Arbor, examined data for the period 2010–2018 from the cross-sectional National Health Interview Survey. Respondents included in the analysis were between the ages of 18 and 21. They were asked whether they had received the HPV vaccine before age 18 and at what age they had been vaccinated against the virus.
The researchers also assessed whether the respondents had received any HPV vaccine dose between the ages of 18 and 21 years. The findings were limited to self-reported vaccination status.
In total, 6606 women and 6038 men were included in the analysis. Approximately 42% of women and 16% of men said they had received at least one HPV vaccine dose at any age. The proportion of female patients who reported receiving an HPV vaccine dose significantly increased from 32% in 2010 to 55% in 2018 (P =.001). Similarly, among men, the percentage significantly increased from 2% in 2010 to 34% in 2018 (P <.001).
Approximately 4% of the female respondents and 3% of the male respondents reported that they had received an HPV vaccine between the ages of 18 and 21 years; 46% of women and 29% of men who received the vaccine between these ages completed the recommended vaccination series.
Findings from the study highlight the continual need for improving vaccination rates among vulnerable populations. Lead study author Michelle Chen, MD, MHS, a professor in the Department of Otolaryngology–Head and Neck Surgery at the University of Michigan, explained in an email to Medscape Medical News that there are multiple barriers to HPV vaccination among young adults. “These barriers to vaccination among young adults primarily include cost, lack of knowledge and awareness, missed opportunities for vaccination, rapidly changing guidelines, and initial gender-based guidelines,” said Chen.
Clinicians play a large role in improving vaccination rates among young adults, who may lack awareness of the overall importance of inoculation against the potentially debilitating and deadly virus. Chen noted that clinicians can lead the way by increasing gender-inclusive awareness of HPV-associated diseases and HPV vaccination, by performing routine vaccine eligibility assessments for young adults regardless of sex, by developing robust reminder and recall strategies to improve series completion rates, and by offering patients resources regarding assistance programs to address cost barriers for uninsured patients.
“Young adult men are particularly vulnerable [to HPV], because they start to age out of pediatric health practices,” added Chen. “Thus, a multilevel gender-inclusive approach is needed to target clinicians, patients, parents, and community-based organizations.”
Gypsyamber D’Souza, PhD, professor of epidemiology at the Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, told Medscape Medical News that the initial uptake of HPV vaccination was slow in the United States but that progress has been made in recent years among persons in the targeted age range of 11 to 12 years. “However, catch-up vaccination has lagged behind, and sadly, we’re still seeing low uptake in those older ages that are still eligible and where we know there still is tremendous benefit,” she said.
D’Souza is a lead investigator in the MOUTH trial, which is currently enrolling patients. That trial will examine potential biomarkers for oropharyngeal cancer risk among people with known risk factors for HPV who came of age prior to the rollout of the vaccine.
She explained that many parents want their children to be vaccinated for HPV after they hear about the vaccine, but because the healthcare system in the United States is an “opt in” system, rather than “opt out” one, parents need to actively seek out vaccination. Children then move toward adulthood without having received the recommended vaccine course. “There are individuals who did not get vaccinated at the ages of 11 and 12 and then forget to ask about it later, or the provider asks about it and the patients don’t have enough information,” D’Souza said.
She noted that one reason why HPV vaccination rates remain low among young adults is that the vaccine is not often kept in stock other than in pediatric clinics. “Because vaccines expire and clinics don’t have a lot of people in that age group getting vaccinated, they may not have it regularly in stock, making this one reason it might be hard for someone to get vaccinated,” she said.
The HPV vaccine is not effective for clearing HPV once a patient acquires the infection, she added. “So young adulthood is a critical time where we have individuals who still can benefit from being vaccinated, but if we wait too long, they’ll age out of those ages where we see the highest efficacy.”
Ultimately, said D’Souza, clinicians need to catch people at multiple time points and work to remove barriers to vaccination, including letting patients know that HPV vaccination is covered by insurance. “There’s a lot of opportunity to prevent future cancers in young adults by having care providers for that age group talk about the vaccine and remember to offer it,” she added.
JAMA. Published online April 27, 2021. Full text
Brandon May is a freelance medical journalist who has written more than 900 articles for medical publications in the United States and the United Kingdom. He resides in downtown Brooklyn, New York City. Twitter: @brandonmilesmay.