A variant first identified in Britain, known as B.1.1.7, is also being found in the U.S., and the modeling indicates that it may worsen the already terrifying spread of the virus across the country, CDC researchers said .
This means that people need to try harder to wear masks, avoid meetings and be socially distant from each other.
“This means that it will be increasingly difficult to control. We will have to take any of these measures to a higher degree, including vaccination,” Dr. Gregory Armstrong, who heads the Office of Advanced Molecular Detection in the Division of Respiratory Diseases at CDC, told CNN.
“Several lines of evidence indicate that B.1.1.7 is transmitted more efficiently than other variants of SARS-CoV-2,” wrote Armstrong and colleagues in the agency’s weekly report, MMWR.
“Variant B.1.1.7 has the potential to increase the path of the pandemic in the United States in the coming months.”
Efforts to vaccinate people – already slower than the federal government expected and promised – need to be stepped up, said the CDC.
“It may be necessary to achieve higher vaccination coverage to protect the public,” wrote the researchers.
The virus has already infected more people in the United States and killed more than in any other country. As of Friday afternoon, according to Johns Hopkins University, the virus was diagnosed in 23 million people in the United States and killed more than 390,000.
Variant B.1.1.7 appears to infect human cells more easily, which would help to infect more people.
It has been detected in about a dozen US states, but the CDC also knows that surveillance is weak and is probably much more common than that. It is also possible that the pattern of mutations that makes the virus more transmissible is appearing independently as it circulates in people, because the more people are infected, the greater the chances of the virus mutating.
The CDC team ran an experimental model to see what could happen in the near future. It is not known how much B.1.1.7 is more transmissible and it is also unknown how much immunity already exists in the US population because of previous infections, so the team made some assumptions. In one scenario, the new variant is 50% more infectious than the dominant variants in circulation.
“In this model, the prevalence of B.1.1.7 is initially low, but because it is more transmissible than the current variants, it shows rapid growth in early 2021, becoming the predominant variant in March”, wrote the CDC team .
“If this behaves as it has done so far in the UK, Denmark and Ireland, yes, it will become an increasing proportion of all cases out there, no matter what we do,” said Armstrong.
“This does not mean that the cases will necessarily increase,” added Armstrong. “It doesn’t mean that we can’t do anything.”
The new variant does not appear to result in higher hospitalization rates or higher death rates, he noted.
“While there is a high likelihood that this will become an increasing proportion of all cases, if we can get people to become more adherent to the recommended measures, the number of cases does not need to increase,” Armstrong said.
In addition, the CDC needs to do more to keep an eye out for new variants and their emergence.
“The CDC also hired several large commercial clinical laboratories to quickly sequence tens of thousands of positive SARS-CoV-2 samples each month and funded seven academic institutions to conduct genomic surveillance in partnership with public health agencies, substantially increasing the availability of timely genomic surveillance data from across the United States, “wrote the team.
The CDC is also eyeing a variant first detected in South Africa and now called B.1.351, in addition to another one found among four travelers from Brazil when they landed in Japan, called B.1.1.28
“These variants carry a constellation of genetic mutations,” wrote the CDC team.
The concerns are that the virus may change in order to help it escape the immunity induced by vaccination, or the immunity introduced with antibody-based treatments. The new coronavirus vaccines are designed to be quick and easy to change to match the new circulating strains, but a major change would mean that people would need to be vaccinated again.
It is also possible that some of the changes make the virus more difficult to detect in standard tests.
And the CDC also fears that if the virus changes in the right way, it could reinfect people who have already recovered from the coronavirus. The flu already does that.