, The New York Times reported late on July 29.
The revelation is one reason the agency reversed course this week and said fully vaccinated people should go back to wearing masks in many cases.
The new findings also are a reversal from what scientists had believed to be true about other variants of the virus, the Times said. The bottom line is that the CDC data show people with so-called breakthrough cases of the Delta variant may be just as contagious as unvaccinated people, even if they do not show symptoms.
ABC News reported earlier on July 29 that the CDC’s updated mask guidance followed an outbreak in Cape Cod, where crowds gathered for the Fourth of July.
As of July 29, 882 people were tied to the outbreak centered in Provincetown, Mass. Of those who live in Massachusetts, 74% were unvaccinated. ABC said the majority were showing symptoms of COVID-19.