Research has been conducted on the effectiveness of the BNT162b2 vaccine against the omicron variant in children. Studies have focused on various age groups, including children 5 to 11 years of age and those under 12 years of age. The research has been published in several medical journals, including the New England Journal of Medicine, Nature, and The Lancet, and has examined vaccine effectiveness in different locations, such as the USA, Malaysia, Hong Kong, and Singapore.