Abstract
Infants aged <6 months are not eligible for covid-19 vaccination. vaccination during pregnancy has been associated with protection against infant covid-19-related hospitalization. the overcoming covid-19 network conducted a case-control study during march 9, 2022-may 31, 2023, to evaluate the effectiveness of maternal receipt of a covid-19 vaccine dose (vaccine effectiveness [ve]) during pregnancy against covid-19-related hospitalization in infants aged><6 months and a subset of infants aged><3 months. ve was calculated as (1 - adjusted odds ratio) x 100% among all infants aged><6 months and><3 months. case-patients (infants hospitalized for covid-19 outside of birth hospitalization and who had a positive sars-cov-2 test result) and control patients (infants hospitalized for covid-19-like illness with a negative sars-cov-2 test result) were compared. odds ratios were determined using multivariable logistic regression, comparing the odds of receipt of a maternal covid-19 vaccine dose (completion of a 2-dose vaccination series or a third or higher dose) during pregnancy with maternal nonvaccination between case- and control patients. ve of maternal vaccination during pregnancy against covid-19-related hospitalization was 35% (95% ci =" 15%-51%)" among infants aged><6 months and 54% (95% ci =" 32%-68%)" among infants aged><3 months. intensive care unit admissions occurred in 23% of all case-patients, and invasive mechanical ventilation was more common among infants of unvaccinated (9%) compared with vaccinated mothers (1%) (p="0.02)." maternal vaccination during pregnancy provides some protection against covid-19-related hospitalizations among infants, particularly those aged><3 months. expectant mothers should remain current with covid-19 vaccination to protect themselves and their infants from hospitalization and severe outcomes associated with covid-19.>
