Effectiveness of COVID-19 vaccination against school absenteeism in children and adolescents hospitalized with COVID-19

Background COVID-19 vaccination has been recommended for children to protect them and to enable in-person educational and social activities. Methods We estimated COVID-19 vaccination effectiveness (VE) against school absenteeism in children 5–17 years old hospitalized from September 1, 2021 through May 31, 2023. Full vaccination was defined as two vaccine doses. Results We studied 231 children admitted to hospital with COVID-19, including 206 (89.2 %) unvaccinated/partially vaccinated and 25 (10.8 %) fully vaccinated. Unvaccinated/partially vaccinated children were absent from school for longer periods compared to fully vaccinated children (median absence: 14 versus 10 days; p-value = 0.05). Multivariable regression showed that full COVID-19 vaccination was associated with fewer days of absence compared to no/partial vaccination on average (adjusted relative risk: 0.77; 95 % CI: 0.61 to 0.98). COVID-19 VE was 50.7 % (95 % CI: −11.3 % to 78.2 %) for school absenteeism above the median duration of absenteeism. Conclusions Full COVID-19 vaccination conferred protection against school absenteeism in hospitalized school-aged children with COVID-19.