On Dec. 29, a National Guardsman in Colorado became the first known case in the United States of a contagious new variant of the coronavirus.

The news was unsettling. The variant, called B.1.1.7, had roiled Britain, was beginning to surge in Europe and threatened to do the same in the United States. And although scientists didn’t know it yet, other mutants were also cropping up around the country. They included variants that had devastated South Africa and Brazil and that seemed to be able to sidestep the immune system, as well as others homegrown in California, Oregon and New York.

Continue reading “How the United States Beat the Variants, for Now” →

A group of 18 scientists stated Thursday in a letter published in the journal Science that there is not enough evidence to decide whether a natural origin or an accidental laboratory leak caused the Covid-19 pandemic.

They argued, as the U.S. government and other countries have, for a new investigation to explore where the virus came from.

The organizers of the letter, Jesse Bloom, who studies the evolution of viruses at the Fred Hutchinson Cancer Research Center in Seattle, and David Relman, a microbiologist at Stanford University, said they strove to articulate a wait-and-see viewpoint that they believe is shared by many scientists. Many of the signers have not spoken out before.

“Most of the discussion you hear about SARS-CoV-2 origins at this point is coming from, I think, the relatively small number of people who feel very certain about their views,” Dr. Bloom said.

Continue reading “Another Group of Scientists Calls for Further Inquiry Into Origins of the Coronavirus” →

Coronavirus variants will pose a continuing threat to the United States, with the potential to spread quickly and blunt the effectiveness of vaccines, scientists told a House panel on Wednesday.

“We must ensure that the tools we use to detect, treat, and forecast the virus are keeping up with emerging variants,” said Rep. Bill Foster, Democrat of Illinois and the chairman of the House subcommittee that heard the scientists’ testimony.

Continue reading “Scientists warn U.S. lawmakers about the continued threat of coronavirus variants.” →

Amid a deepening crisis in India, the World Health Organization announced Monday that it had designated the B.1.617 variant, which has been growing more common in the country, as a variant of concern. Scientists still don’t know much about the variant, but they are worried that it might be helping to fuel the rise in the nation’s coronavirus infections, which experts say are probably undercounted.

“There is increased transmissibility demonstrated by some preliminary studies” of the variant, said Dr. Maria Van Kerkhove, the technical lead of the W.H.O.’s coronavirus response.

Continue reading “A coronavirus variant first found in India is now officially a ‘variant of concern,’ the W.H.O. said.” →