The highly transmissible delta variant of the coronavirus is spreading like wildfire throughout the US, raising further concern for areas with low vaccination rates and renewing scrutiny of federal mask guidance.
The delta variant, first identified in India, now makes up more than 20 percent of cases in the US, with some estimates rising to at least 37 percent in recent days. The variant is rapidly overtaking the previously predominant variant in the US, Alpha, which was first identified in the UK and dominated the US in a matter of months this past spring. Scientists estimate that the alpha variant is around 50 percent more contagious than the original SARS-CoV-2 virus that exploded out of Wuhan, China.
Delta, on the other hand, is estimated to be 50 percent to 60 percent more contagious than Alpha. That is, it may be more than twice as contagious as the original virus.