Impact of the COVID-19 Pandemic on Routine Childhood Vaccination in Oklahoma

Background/Objectives: The COVID-19 pandemic substantially disrupted routine childhood vaccination practices across the United States. Oklahoma, a state characterized by lower socioeconomic indicators and higher levels of vaccine hesitancy, may have been particularly vulnerable to these disruptions. This study aimed to assess the impact of the COVID-19 pandemic on routine childhood vaccination in Oklahoma. Methods: Data were obtained from the Oklahoma State Immunization Information System to examine changes in the administration of DTaP and MMR vaccines before and during the COVID-19 pandemic, stratified by pandemic phase. Percentage changes in vaccine doses administered were calculated across time periods. Log-binomial regression models were used to evaluate the association between pandemic timing and receipt of subsequent DTaP doses among children under one year of age. Results: Administration of both DTaP and MMR vaccines declined during the COVID-19 pandemic across all pandemic phases examined. Compared with the pre-pandemic period, fewer children returned for subsequent DTaP doses during the pandemic. Regression analyses indicated a reduced likelihood of completing age-appropriate DTaP dosing among infants during the pandemic. Conclusions: Routine childhood vaccination in Oklahoma declined during the COVID-19 pandemic, with persistent reductions observed across pandemic phases. These findings highlight vulnerabilities in vaccination delivery during public health emergencies and underscore the need for targeted state-level strategies to sustain routine immunization services during future crises.