The effectiveness of the Pfizer-BioNTech COVID-19 vaccine against Omicron “declined rapidly for children, particularly those 5-11 years,” according to a study released February 28. The authors of the study still recommended the vaccine for that age group, stating it was protective against severe disease. They also proposed the recommended dose for 5- to 11-year-olds was too small, suggesting a higher dose might solve the problem.