LELAND, MISSISSIPPI – APRIL 29: Medical workers with Delta Health Center prepare to vaccinate people at a pop-up COVID-19 vaccination clinic in a rural Delta community on April 29, 2021 in Leland, Mississippi. An estimated 23 percent of Mississippians are fully vaccinated against COVID-19, and the Mississippi State Department of Health has reported a total of 334 new cases with the numbers currently trending up. Mississippi, a southern state with pockets of entrenched poverty, has struggled to vaccinate residents in remote areas who may not have access to the internet or transportation. (Photo by Spencer Platt/Getty Images)