Delta variant now represents 83% of sequenced samples in US, CDC director says

The Delta variant of Covid-19 now makes up more than 80% of sequenced samples in the United States, US Centers for Disease Control and Prevention Director Dr. Rochelle Walensky said Tuesday. 

“CDC has released estimates of variants across the country and predicted the Delta variant now represents 83 percent of sequenced cases,” she said in a Senate Committee on Health, Education, Labor, and Pensions hearing. “This is a dramatic increase, up from 50 percent for the week of July 3."

The CDC’s variant-tracking webpage has not yet updated it’s Nowcast variant estimate data for the last two weeks. 

The most recent data from Israel evaluating effectiveness of Pfizer’s mRNA Covid-19 vaccine against the Delta variant found the vaccine to be 64% protective against infection, and that the vaccine is 93% effective in preventing severe disease and hospitalizations.