Why vaccine doses differ for babies, kids, teens and adults – an immunologist explains how your immune system changes as you mature Posted byBrian Peppers November 3, 2021 Leave a comment on Why vaccine doses differ for babies, kids, teens and adults – an immunologist explains how your immune system changes as you mature First CDC signed off on a COVID-19 vaccine for adults, then teens. Now US children ages 5 to 11 are officially eligible for shots. Here’s the science on why each…