The B117 SARS-CoV-2 variant, identified in 33 states thus far, will dominate other strains in the coming weeks, triggering major COVID-19 surges such as those seen in Portugal and the United Kingdom—unless the United States immediately scales up surveillance and mitigation efforts, according to a study published yesterday on the preprint server medRxiv.A team led by scientists from the Scripps Research Institute sequenced SARS-CoV-2 genomes from 10 states using US COVID-19 testing facilities to track the emergence and spread of B117, the more transmissible and lethal variant that was first discovered in the United Kingdom in September and likely introduced to the United States during holiday travel.Among the 460 SARS-CoV2 samples