Vaccine Completion and Timeliness Among Children in the Military Health System: 2010-2019

Abstract

Objective: Few studies have evaluated pediatric vaccination coverage in the Military Health System, although some evidence suggests lower than ideal coverage. This study assessed vaccine completion and timeliness among military dependents through age 24 months.

Methods: Children born at military hospitals from 2010 through 2019 were identified using Department of Defense Birth and Infant Health Research program data. Vaccine completion and timeliness were assessed for diphtheria, tetanus, and pertussis; polio; measles, mumps, and rubella; hepatitis B; Haemophilus influenzae type b; varicella; and pneumococcal conjugate individually and as a combined 7-vaccine series; rotavirus was assessed separately. Modified Poisson regression models were used to calculate risk ratios (RRs) and 95% confidence intervals (CIs) for noncompletion and delays, adjusting for demographic characteristics.

Results: Of 275 967 children, 74.4% completed the combined 7-vaccine series, and 36.2% of those who completed the series had delays. Completion peaked at 78.7% among children born in 2016 and 2017. Among all vaccines, completion was lowest for rotavirus (77.5%), diphtheria, tetanus, and pertussis (83.1%), Haemophilus influenzae type b (86.6%), and pneumococcal conjugate (88.4%). Risk for noncompletion was higher among children born to younger pregnant parents (adjusted RR = 1.33; 95% CI = 1.27-1.40) and with a well-child care location change (adjusted RR = 1.10; 95% CI = 1.09-1.12). Risk for delays paralleled that for noncompletion.

Conclusions: Vaccine completion and timeliness generally improved among military children, but greater noncompletion of vaccine series with more versus fewer doses and disparities for younger and mobile service members suggest system barriers remain.