The more contagious variant of coronavirus that was identified in the UK, the B-117 variant, has become the dominant strain in the U.S., CDC director Rochelle Walensky said on Wednesday.
In late February, the B-117 variant accounted for around 11% of all cases but by mid-March that had jumped to 27%.
Experts believe the B-117 variant is more contagious and likely more deadly, which could help explain why its increasing prevalence in the U.S. has coincided with a rise in cases despite the speed of vaccinations, which have proven effective against the variant.
“We know that these increases are due, in part, to more highly transmissible variants, which we are very closely monitoring,” Walensky said at a White House briefing earlier this week.
