A COVID-19 patient in an ICU unit in a hospital in Capetown, South Africa, in December 2020. A variant emerged in South Africa that has since spread to other parts of the world. Other new variants could emerge elsewhere. Rodger Bosch/AFP via Getty ImagesSpring has sprung, and there is a sense of relief in the air. After one year of lockdowns and social distancing, more than 171 million COVID-19 vaccine doses have been administered in the U.S. and about 19.4% of the population is fully vaccinated….