evidence: In December 2020, the Pfizer-BioNTech COVID-19 vaccine two-dose series was found to be both safe and effective in preventing COVID-19 infection in people age 18 and older. This data helped predict how well the vaccines would work for younger people. The effectiveness varied by age. Since 2020, the vaccine has been updated yearly to better protect against the strains of COVID-19 spreading in the community. The currently approved vaccine is Pfizer-BioNTech COVID-19 vaccine 2024-2025 formula. The Pfizer-BioNTech vaccine is approved under the name Comirnaty for people age 12 and older. The FDA authorized the vaccine for people age 6 months to 11 years. The number of shots in this vaccination series varies based on a person's age and COVID-19 vaccination history. [...] But vaccines are not 100% effective. So taking other action to lower your risk of getting COVID-19 still helps protect you and others from the virus. These steps are even more important when you're in an area with a high number of people with COVID-19 in the hospital. Protection also is important as time passes since your last vaccination.