Why older teens miss key vaccines

Few teenagers complete the entire meningococcal vaccines (MenACWY) series as recommended, according to a new report.

The study, published in the Journal of Adolescent Health, found that whereas many teenagers receive the initial doses of the vaccine, only about two-thirds complete the series-partly due to a decline in the number of preventive visits and also to fewer other vaccines being offered during this period.¹

“MenACWY vaccine uptake was significantly higher in younger adolescents compared with older adolescents, even after accounting for demographic and healthcare utilization characteristics,” says Samantha Kurosky, MSPH, senior director of health economics for RTI Health Solutions and lead author of the study. “Older adolescents are utilizing less preventive care services and seeing fewer traditional vaccinating physicians compared with younger adolescents, which may be leading to fewer opportunities for offering the MenACWY vaccine.”

The Advisory Committee on Immunization Practices (ACIP) began recommending routine meningococcal vaccines covering serogroups A, C, W, and Y in 2010. The vaccine is meant to be administered between ages 11 and 13 years initially with boosters at ages 16 to 18 years. No booster is required for teenagers who are not high risk and receive the first vaccine dose after age 16 years, the report notes.

Although the meningococcal conjugate vaccine (MenACWY) is recommended at age 11 to 12 years with a booster at age 16 years, national data suggest that uptake is lower in older teenagers than in younger age groups. The new study sought to investigate MenACWY uptake among older teenagers using Commercial Claims and Encounters (CCAE) and Medicaid MarketScan databases from 2011 to 2016. Researchers studied when adolescents received the MenACWY vaccine, factors associated with vaccination, missed opportunities, and differences between the age groups that may have led to disparities.

Vaccine uptake down for older teenagers

The research team found that, overall, younger teenagers were more likely to receive the MenACWY vaccine. This difference was largely attributed to differences between younger and older adolescents in the number of non–MenACWY vaccines received, the number of preventive care/well-child visits they attended, and the type of healthcare provider most frequently visited during their respective age ranges.

“Uptake increased over time in both age groups, but there is room for improvement,” Kurosky says. “Our research showed some unvaccinated individuals did not get the vaccine even if they had a preventive care visit. The lack of preventive care visits for a substantial number of adolescents in both age groups is also an issue.”

The need for full vaccination is critical, with serogroups C, W, and Y-all covered by the vaccine-accounting for nearly half of the meningococcal disease cases in children aged 11 years and older in 2017, according to the report.

The study investigated the records of more than 376,000 younger teenagers and 419,000 older adolescents and found that uptake was lower in older groups than in younger groups despite gender or insurance type (private insurance versus public). There were some differences in geographic areas, the report notes, with uptake being somewhat higher in urban areas compared with rural, and uptake increasing overall in the more recent years of the study. The 2017 National Immunization Survey-Teen (NIS-Teen) reveals that 83.6% of adolescents overall had received at least 1 dose of MenACWY by age 13 years, but only 44.3% of teenagers had received both the initial and booster doses by age 17 years.

In the CCAE sample, nearly 92% of younger teenagers received the MenACWY between the ages of 11 and 12 years compared with a 64.2% vaccination rate for the booster vaccine among 17- to 18-year-olds. Pediatricians were the ones to administer most of the vaccines in the younger cohort, the study notes, but performed fewer vaccinations in the older group. The study also notes that vaccination occurred most often for both groups in conjunction with well visits and other vaccinations, which may explain why fewer older teenagers receive booster vaccination, according to the report.

More reasons for decreasing rates

Whereas preventive care visits are recommended through age 21 years by the American Academy of Pediatrics (AAP), the study team notes that a drop in preventive care visits, as well as the slowing down of routine vaccinations in the later teenaged years, both likely contribute to a drop in meningococcal vaccination as these children age. Missed preventive encounters were nearly 3 times higher in older teenagers, the study notes. Additionally, older teenagers tend to have fewer visits with pediatric providers, leading to more missed opportunities, according to the report. The study notes that 31.9% of older teenagers and 21.6% of younger teenagers were unvaccinated despite having at least 1 preventive or well-care visit during the study period.

“MenACWY vaccine uptake was significantly higher in younger adolescents compared with older adolescents, even after accounting for demographic and healthcare utilization characteristics. Younger adolescents benefit from better adherence to preventive care recommendations,” Kurosky says. “This may be because healthcare providers tie the annual preventive healthcare visit to the recommended vaccination schedule in early adolescence. A similarly established focus on pairing preventive care and vaccination did not exist during older adolescence-a time when fewer vaccinations are recommended-which may in part explain our finding that a substantial proportion of older adolescents had a preventive care visit, yet never received the vaccine and that many older adolescents never attended a preventive care visit.”

How to increase vaccination rates

The study notes that vaccination rates may be increased by solidifying a vaccine platform at ages 16 to 18 years, as well as supporting the need for preventive care in the later teenaged years.

“Increasing MenACWY uptake in older adolescents might benefit by a similarly focused effort for preventive care and vaccination at ages 16 to 18 years-a time when a child is insured through a parent/guardian or eligible for the Vaccines for Children program and likely receiving care from a primary care provider,” Kurosky says. “For example, a regular preventive care visit at age 16 years could include the MenACWY booster and the meningococcal serogroup B (MenB) vaccine, which may be given to adolescents and young adults aged 16 to 23 years, as well as routine or catch-up flu, Tdap, and HPV vaccines.”

Kurosky says she hopes the report will spur additional research and attention to both meningococcal vaccination and healthcare utilization in the later teenaged years.

“Results from this study provide large-scale, contemporary evidence on the role of healthcare utilization in MenACWY vaccination among adolescents. The results may further support development of targeted interventions that leverage current preventive care recommendations and inform new policies and strategies toward improving vaccination in harder-to-reach adolescent populations,” Kurosky says.

“We hope our findings highlight the importance of following the American Academy of Pediatrics’ recommendations for annual preventive care visits during adolescence to increase the opportunity for vaccination,” Kurosky notes. “Additionally, working with nonpediatric providers to assess vaccine eligibility and administer vaccines, or refer eligible patients to a provider who vaccinates, may improve access to vaccination, particularly among older adolescents.”

References:

1. Kurosky SK, Esterberg E, Irwin DE, et al. Meningococcal vaccination among adolescents in the United States: a tale of two age platforms. JAdolesc Health. 2019;65(1):107-115.