evidence: The CDC's current definition of "fully vaccinated" is two shots of the mRNA vaccines, Pfizer and Moderna or one shot of J&J. Those aged 5 and up are eligible for booster shots at least five months after a second dose of the mRNA vaccines or two months after a J&J shot. [...] Since the start of the COVID vaccination campaign, health officials focused on reaching older Americans, who are at high risk of severe disease. People over 65 have the highest vaccination rates in the U.S., while kids under age 12 have the lowest. (5-to-11-year-olds were first eligible for the vaccine starting in fall 2021. Children younger than 5 could receive the vaccine starting in June 2022.) [...] States receive vaccine allocations from the federal government and make their own plans for how to get those vaccines out to residents. Some states are encountering hesitancy and resistance to getting vaccinated among their populations.