Thanks to sequencing by @UWVirology, @CDCgov and @seattleflustudy we have genomes for 39 viruses sampled from WA. Importantly 35 of these 39 viruses (90%) fall into a single genetic cluster indicating a single ~Jan introduction from China and subsequent local spread. 3/8 pic.twitter.com/LrEhdo5Sol— Trevor Bedford (@trvrb) March 16, 2020