AdvertisementYou Think The U.S. Has Vaccine Issues? 130 Countries Haven't Even Started VaccinatingFebruary 14, 2021Jason BeaubienfacebookEmailA health worker inoculates 72-year-old Olga D'arc Pimentel with a dose of Oxford-AstraZeneca's COVID-19 vaccine. She lives on the banks of the Rio Negro near Manaus, Brazil. A small study in South Africa has raised concerns about the AstraZeneca vaccine's effectiveness. (AFP via Getty Images)