CDC Internal Report: Delta As Contagious As Chickenpox

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The supercharged Delta variant of COVID-19 is as contagious as chickenpox and may spread as easily from vaccinated persons as the unvaccinated, according to a new internal report from the Centers for Disease Control and Prevention.

The document, based on yet-to-be published studies, urges health officials to acknowledge that “the war has changed” thanks to Delta, the COVID variant that has quickly gained ground across the country and much of the rest of the world. “I think people need to understand that we’re not crying wolf here. This is serious,” CDC Director Rochelle Walensky told CNN. “It’s one of the most transmissible viruses we know about. Measles, chickenpox, this — they’re all up there.”

While those who are vaccinated are three times less likely to get COVID-19 than those without the jab (and ten times less likely to get severe COVID or die), according to the report, vaccinated people who contract COVID are just as contagious as unvaccinated people. Each person infected with a case of Delta, on average, infects eight or nine others, CNN reports. 

“My overall take: As the document says, ‘the war has changed.’ Data argues that universal masking is critical to block spread of delta – a more infectious, and possibly more serious virus – particularly if it’s true that vaccinated folks can be part of the chain of spread,” tweeted Robert Wachter, chairman of the Department of Medicine at the University of California at San Francisco, who was not involved in the report. He added that “the foe has gotten better at its job” and, consequently, a more aggressive vaccination strategy is needed.

Alarm over the report’s findings among CDC scientists reportedly drove their decision to update the agency’s masking recommendations earlier this week, urging all Americans — regardless of vaccination status — to resume mask-wearing in indoor public spaces in regions with high coronavirus transmission.

CDC Internal Report: Delta As Contagious As Chickenpox