THE The Centers for Disease Control and Prevention have been warning about this since January: a more contagious and possibly deadly variant of the coronavirus, found for the first time in Britain, is likely to become prevalent in the United States, perhaps leading to a violent increase in cases. and deaths.
The first part of this warning appears to be coming true: the variant, known as B.1.1.7, is doubling its share of all new cases in the United States every 10 days.
But the second part is more difficult to decipher, at least so far. The sharp drop in new cases since the peak of January stopped in mid-February, but the trend has since been almost stable or only slightly downward, rather than a dreaded “fourth wave”.
Experts are not sure why. The fast pace of vaccinations and other measures to control the virus in much of the country may be balancing the spread of the most contagious variant, so that the total number of cases does not rise or fall too much. But it is difficult to know how long this balance can last or whether the next clear curve in the trend will be up or down.
The risk of an outbreak has by no means passed, Dr. Anthony S. Fauci, President Biden’s chief medical advisor at Covid-19, warned on Sunday.
The nation was on average about 60,000 new cases per day starting on Saturday, according to a New York Times database. This is the lowest seven-day average since October and about 10% below the February 21 average, when the decline slowed. Still, the number is close to the peak of the peak last summer. Death reports are also falling, but remain high, regularly reaching 2,000 a day.
In an interview on Sunday on CBS’s “Face the Nation” program, Dr. Fauci said that in the past week and a half, the decline in the number of cases has stalled. “We are stagnating at a very high level – 60 to 70,000 new infections per day is quite high,” he said.
This trend is particularly worrying, he said, because in the United States over the past year, when the daily level of new infections has stabilized at a high level, outbreaks of cases have emerged. And recently, in Europe, infection levels have decreased, then stabilized and “in the past week or so, they have seen an increase of about 9% in cases,” said Fauci.
Experts say they need more data to understand why the United States has yet to see an increase in cases, as the fearsome variant B.1.1.7 has spread so quickly, already accounting for more than a fifth of new cases.
William Hanage, a Harvard epidemiologist, said there may be several reasons why B.1.1.7 did not begin to devastate the United States in the way it consumed Britain, including wider vaccination, improved weather and the patchwork. of pandemic restrictions in all states.
Florida, say Hanage and other experts, is an interesting example, because infections have not increased, although restrictions are more flexible than in other states, and the variant represents at least about 30% of cases, the largest proportion in the country. .
Dr. Fauci said on Sunday that a variant first identified in New York “is not yet widespread, but appears to be spreading quite efficiently across the metropolitan area of New York and beyond.”
He said there is evidence that the variant may partially circumvent the protection afforded by vaccines and treatments with monoclonal antibodies, although the variant does not avoid vaccines and treatments as much as a first identified in South Africa.
The best way to prevent spread is to “vaccinate people as quickly and expeditiously as possible and, above all, to maintain the public health measures that we talk about so much: masking, physical distance and prevention of congregational environments, especially within from home. “Dr. Fauci said.” This is what you can do to prevent the spread of a worrying variant. ”