Fast-Spreading Covid Variant Seen Becoming Top U.S. Strain
Several lines of evidence indicate the strain spreads faster than other versions, and steps should be taken to reduce its transmission, including increased genomic surveillance and adherence to public-health measures like testing and mask-wearing, the U.S. Centers for Disease Control and Prevention said Friday in the report.
“Increased SARS-CoV-2 transmission might threaten strained health-care resources, require extended and more rigorous implementation of public-health strategies, and increase the percentage of population immunity required for pandemic control,” the report said.
The variant, called B.1.1.7, has already been spotted in the U.S., with about 76 cases confirmed in the country to date, according to the CDC. The agency’s projection was based on modeling that showed rapid growth of the variant early this year, which could further undermine the rollout of Covid-19 vaccines that’s been marked by missed deadlines and underuse of supplies.
The variant currently makes up less than about 0.5% of circulating viruses, the agency estimated in the report, although the exact prevalence of B.1.1.7 in the U.S. is not currently known.
U.K. health officials have attributed a recent surge in cases to the variant’s ability to spread and have imposed strict lockdown measures. British Chief Medical Officer Chris Whitty warned that, while he expects “things are going to improve in the spring,” the variant might make the reopening of the economy more difficult.
The variant “has the potential to increase the U.S. pandemic trajectory in the coming months,” the report said.
Viruses mutate frequently and variants are to be expected, but new variants could potentially take forms that would evade current tests and therapeutics for Covid-19. The B.1.1.7 variant is one of several that have been detected around the world, though neither a variant known as B.1.351 found in South Africa nor another variant called B.1.1.28 have been found in the U.S. as of mid-January, the CDC said.
The B.1.1.7 variant’s high contagiousness calls for even more rigorous application of public-health measures like vaccination, distancing, masking and hand-washing to control spread, the CDC said. Those public-health measures should be taken “sooner rather than later” to stem its spread, and the health system should be prepared for further surges in cases, the regulator said.
“Increased transmissibility also means that higher than anticipated vaccination coverage must be attained to achieve the same level of disease control to protect the public compared with less transmissible variants,” the report said.
The CDC also said it’s working with partners in academia, industry and at the state and local level to sequence the genomes of the virus, which can spot the appearance of new strains.