U.S. coronavirus cases trend upward — with nearly 80,000 new infections reported Thursday — health officials are warning about the spread of multiple, more transmissible variants, some of which have seeded outbreaks in states such as Michigan and California.
For the first time the P.1 variant that originated in Brazil has taken the No. 2 spot. At least 434 people in the United States have been infected with the variant, which has devastated Brazil, with the largest number of cases found in Massachusetts, Illinois and Florida.