Coverage and correlates of COVID-19 vaccination among children aged 5-11 years in Alberta, Canada

Background and Objectives In Alberta, Canada, the COVID-19 vaccination program for children aged 5-11 years opened on November 26, 2021. Our objectives were to determine the cumulative vaccine coverage, stratified by age, during the first seven months of vaccine availability, and investigate factors associated with vaccine uptake. Methods This retrospective cohort study used population-based administrative health data to assess COVID-19 vaccination coverage among children aged 5-11 years in Alberta, Canada. We determined cumulative vaccine coverage since the time of vaccine availability and used a modified Poisson regression to evaluate factors associated with vaccine uptake. Results Of 377,753 eligible children, 43.8 % (n=165,429) received one or more doses of COVID-19 vaccine during the study period (11.2% received only one dose, while 32.5 % received 2 doses). Almost 90% of initial doses were received within the first two months of vaccine availability. Of those eligible for a second dose, only 75.1% (n=122,973) received it during the study time period. We found a step-wise relationship between increasing child age and higher vaccine coverage. Other factors associated with higher vaccine coverage included living in a neighborhood with higher income, in a more densely populated area, and in certain geographic health zones. Registration in a private school was associated with lower vaccine coverage. Conclusions Messaging around COVID-19 vaccine safety and need should be tailored to child age, rather than uniform across the 5-11 year age range. Opportunities for targeted vaccination interventions should be considered.