A health worker applies a dose of the AstraZeneca vaccine during the first day of a three-day COVID-19 vaccination campaign for people over age 35 in the Complexo da Maré favela of Rio de Janeiro, Brazil, Brazil, Thursday, July 29, 2021. Some recipients will be monitored to study the rate of protection the vaccines provide and the extent to which virus variants are circulating. (Photo by Bruna Prado/AP Photo)

A frontline worker reacts as she receives a dose of AstraZeneca's COVISHIELD vaccine, produced by the Serum Institute of India, during the coronavirus disease (COVID-19) vaccination campaign at a medical centre in New Delhi, India, February 24, 2021. (Photo by Anushree Fadnavis/Reuters)

A health worker pretends to give a shot to a girl's doll to help put her at ease before giving her a shot of the Coronavac vaccine for COVID-19, at a sports center as children age 5 – 11 start getting vaccinated in Asuncion, Paraguay, Monday, January 31, 2022. (Photo by Jorge Saenz/AP Photo)

A health worker gives a polio vaccine to a girl on a street in Lahore, Pakistan, Monday, June 27, 2022. Pakistan launched a new anti-polio drive on Monday, with the goal to vaccinate a million children across Pakistan. (Photo by K.M. Chaudary/AP Photo)

Medical staff administering the dose of Moderna COVID-19 Vaccine at the M A G Osmani Medical College & Hospital vaccination center in Sylhet, Bangladesh on July 26, 2021. (Photo by Md Rafayat Haque Khan/ZUMA Press Wire/Rex Features/Shutterstock)

A little girl holding her newborn sister waits for their turn in a queue during a vaccination campaign under the supervision of the Syrian Arab Red Crescent (SARC) humanitarian nonprofit organization, in the besieged Syrian town of Douma, Syria, 23 May 2017. According to a statement from SARC, in the city of Douma some 12,809 children under the age of five were immunized in a vaccination campaign to prevent measles and poliomyelitis. The campaign was the first of its kind with the participation of 100 volunteers. SARC has been delivering vaccines to 17 health centers approved for vaccination campaigns in towns and villages in the Eastern Ghouta area. (Photo by Mohammed Badra/EPA)

Coronavirus vaccinated audience members watch Saudi prominent singer Mohammed Abdu as he performs at the newly built Super Dome, in Jiddah, Saudi Arabia, late Thursday, July 8, 2021. The concert is organized by the Saudi General Entertainment Authority after the kingdom lifted coronavirus restrictions on events in May. (Photo by Amr Nabil/AP Photo)

Participants celebrate the awakening of the Hoppeditz, a fictional character whose return to life marks the start of the carnival season in Düsseldorf, western Germany on November 11, 2021. The 11.11. is celebrated this year again under Corona conditions in presence. However, in the carnival strongholds of Cologne and Düsseldorf, this only applies to the vaccinated and the recovered. (Photo by Federico Gambarini/dpa/Alamy Live News)