Steven Grimmett, a microbiologist on the COVID-19 team at the Washington State Department of Health's Public Health Laboratory, is seen through a window of a machine that identifies positive and negative COVID-19 cases, Dec. 7, 2021, in Shoreline, Wash. Scientists are warning that omicron’s lightning-fast spread across the globe practically ensures it won’t be the last worrisome coronavirus variant. And there’s no guarantee the next ones will cause milder illness or that vaccines will work against them. (AP Photo/Ted S. Warren)
