The agency heightened concerns about the spread of the virus in its report on Friday and even urged jurisdictions with undetectable levels of the virus to take precautionary measures. But the CDC’s internal document sounded much more alarmed, advocating universal masking – for all, regardless of local broadcast strength – and recommending that the agency “recognize that the war has changed”.
July 30, 2021, 1:11 p.m. ET
With the number of daily cases averaging nearly 72,000 cases (as of Friday), vaccinated people with young children, aging parents or friends and family members with weak immune systems may have to wear masks to protect vulnerable people around them – even in communities with lower infection rates .
Indeed, the questions Americans now face seem almost inexhaustible, almost insoluble. Should companies really bring employees back to work when vaccinated people could occasionally spread the variant? What does this mean for shops, restaurants, schools? Are unmasked family celebrations off the table again?
Delta’s unpredictability has humiliated scientists who expected the virus to cause mostly sporadic outbreaks in areas with low vaccination rates. In the UK, where the variant seems to have subsided after an increase, vaccinations have been introduced by age and a much higher proportion of people over 50 are vaccinated than in the United States.
But vaccination rates are much more patchy in the United States, said Bill Hanage, an epidemiologist at Harvard TH Chan School of Public Health. “The result is that what Delta is doing in the UK is not necessarily what it will be doing in places with very different vaccinations,” he said.
“Things are getting worse than they would have been,” without the variant, he added. “But they will be much better than they would have been without the vaccination.”
Understand the state of vaccine mandates in the United States
In the report released on Friday, the agency described a single outbreak in Provincetown, Massachusetts, which quickly grew to nearly 469 cases in the state by Thursday, three-quarters of which were fully immunized.