A variant first identified in Britain, known as B.1.1.7, is also found in the US, and modeling indicates it could exacerbate the already terrible spread of the virus across the country, said the CDC researchers.
That means people have to try harder to wear masks, avoid gatherings, and stay socially distant.
“It means that it will be increasingly difficult to control. We will have to do each of those measures to a greater degree, including vaccination,” says Dr. Gregory Armstrong, who heads the Office of Advanced Molecular Detection at CDC’s respiratory disease department, told CNN.
“Multiple evidence indicates that B.1.1.7 is more efficiently transmitted than other SARS-CoV-2 variants,” Armstrong and colleagues wrote in the agency’s weekly report, the MMWR.
“Variant B.1.1.7 has the potential to extend the pandemic trajectory in the US in the coming months.”
Efforts to vaccinate people – slower than the federal government hoped and promised – must be ramped up, the CDC said.
“Higher vaccination coverage may need to be achieved to protect the public,” the researchers wrote.
The virus has already infected and killed more people in the US than in any other country. According to Johns Hopkins University, the virus was diagnosed Friday afternoon in 23 million people in the US and more than 390,000 people had died.
The B.1.1.7 variant appears to infect human cells more easily, which could allow it to infect more people.
It has been detected in about a dozen US states, but the CDC also knows that surveillance is poor and is likely to be much more common than that. It is also possible that the mutational pattern that makes the virus more transmittable arises independently because it circulates among humans, because the more people infected, the more likely the virus is to mutate.
The CDC team has run an experimental model to see what could happen in the near future. It’s not known how much more transmissible B.1.1.7 is, nor is it known how much immunity there is already in the U.S. population from previous infections, so the team made some assumptions. In one scenario, the new variant is 50% more contagious than the currently dominant variants in circulation.
“In this model, the prevalence of B.1.1.7 is initially low, but because it is more transmittable than the current variants, it shows rapid growth in early 2021 and becomes the predominant variant in March,” the CDC wrote. -team.
“If this behaves as it has done so far in the UK, Denmark and Ireland, it will indeed become an increasing and increasing proportion of all cases, no matter what we do,” Armstrong said.
“That’s not to say cases will necessarily increase,” Armstrong added. “That doesn’t mean we can’t do anything.”
The new variant does not appear to result in higher hospital admissions or higher death rates, he noted.
“While this is likely to become an increasing proportion of all cases, there is no need for the number of cases to increase if we can get people to follow recommended measures more closely,” Armstrong said. said.
In addition, the CDC must do more to keep an eye out for new variants and their appearance.
CDC has also contracted with several large commercial clinical laboratories to rapidly sequence tens of thousands of SARS-CoV-2 positive specimens each month and has funded seven academic institutions to conduct genomic surveillance in collaboration with public health agencies, contributing significantly To the availability of current genomic surveillance data from across the United States, ”the team wrote.
The CDC is also keeping an eye out for a variant first spotted in South Africa and now called B.1.351, plus a variant spotted among four travelers from Brazil when they landed in Japan called B.1.1 .28.
“These variants carry a constellation of genetic mutations,” the CDC team wrote.
The concerns are that the virus could change in ways that would help it evade the immunity caused by vaccination, or the immunity caused by antibody-based treatments. The new coronavirus vaccines are designed to adapt quickly and easily to new circulating strains, but a major change would require people to be re-vaccinated.
It is also possible that some changes can make the virus more difficult to detect in standard tests.
And the CDC is also concerned that if the virus changes just the right way, it could re-infect people who have already recovered from the coronavirus. Influenza is already doing this.