cdc says new covid strain in uk could already be circulating undetected in u.s .
cdc says new covid strain in uk could already be circulating undetected in u.s .
while the variant hasn't been found in the u.s. yet, the cdc noted that scientists haven't sequenced the genetic coding for many covid-19 infections here.", "\"given the small fraction of us infections that have been sequenced, the variant could already be in the united states without having been detected.\"")