Health workers Diego Feitosa Ferreira, 28, right, and Clemilton Lopes de Oliveira, 41, leave a home after a resident denied to be vaccinated against the new coronavirus, in the Capacini community, along the Purus river, in the Labrea municipality, Amazonas state, Brazil, Friday, Feb. 12, 2021. Getting the vaccine to the world's farthest corners means delivering it by boat to Maine's islands, traveling by snowmobile to villages in Alaska and navigating complex waterways in Brazil's Amazon. (AP Photo/Edmar Barros)