A child receives a dose of the COVID-19 vaccine at a vaccination center in Cascais, Portugal, on Dec. 18, 2021. Portugal started vaccinating children between the ages of five and 11 against COVID-19 from Saturday. (Photo by Pedro Fiuza/Xinhua)
A child receives a dose of the COVID-19 vaccine at a vaccination center in Cascais, Portugal, on Dec. 18, 2021. Portugal started vaccinating children between the ages of five and 11 against COVID-19 from Saturday. (Photo by Pedro Fiuza/Xinhua)
Children wait to receive the COVID-19 vaccine at a vaccination center in Cascais, Portugal, on Dec. 18, 2021. Portugal started vaccinating children between the ages of five and 11 against COVID-19 from Saturday. (Photo by Pedro Fiuza/Xinhua)
Children are seen with their parents after receiving the COVID-19 vaccine at a vaccination center in Cascais, Portugal, on Dec. 18, 2021. Portugal started vaccinating children between the ages of five and 11 against COVID-19 from Saturday. (Photo by Pedro Fiuza/Xinhua)
A child receives a dose of the COVID-19 vaccine at a vaccination center in Cascais, Portugal, on Dec. 18, 2021. Portugal started vaccinating children between the ages of five and 11 against COVID-19 from Saturday. (Photo by Pedro Fiuza/Xinhua)
A child receives a dose of the COVID-19 vaccine at a vaccination center in Cascais, Portugal, on Dec. 18, 2021. Portugal started vaccinating children between the ages of five and 11 against COVID-19 from Saturday. (Photo by Pedro Fiuza/Xinhua)