Chicago Mayor Lori Lightfoot said the city's health department is following news of a new and potentially more contagious strain of coronavirus in the United Kingdom "very, very closely."
Lightfoot said the city has been monitoring the latest development prior to current reporting and said the city is prepared to "take all action that's necessary."
"We are following this very closely, we're digging down," Lightfoot said during an unrelated press conference Monday. "I don't think we know enough yet about what this potential new strain is, how it's transmitted, but believe me, we are following very closely, and we will take all action that's necessary to protect the public."
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So far, British Airways will require travelers to test negative for the coronavirus before boarding flights bound for New York's John F. Kennedy International Airport, New York Gov. Andrew Cuomo said Monday. Cuomo said at a press briefing that he also asked Delta Air Lines and Virgin Atlantic to abide by the same requirements.
Moncef Slaoui, the chief science adviser for the U.S. government’s COVID-19 vaccine effort, said scientists are still working to confirm whether the virus strain in the United Kingdom spreads more easily.
Although that could be why it has become more prevalent in the U.K., Slaoui said in a briefing with reporters Monday that another possible explanation is that “seeding happened in the shadows” before scientists started looking for it.
Animal studies are needed to confirm that the strain spreads more easily. Slaoui said that process takes several weeks.
In the meantime, he said there is no evidence the variant causes more severe disease or is more deadly. He also said the expectation is that vaccines would still be effective against the virus strain, but that scientists are working to confirm that.
Dr. Scott Gottlieb, a former U.S. Food and Drug Administration commissioner and a board member of Pfizer, told CNBC Monday that the evidence does suggest the new variant transmits more easily. But, he cautioned, "it doesn't seem to have mutated the surface proteins of the virus in a way that they would slip past our vaccines or prior immunity. In fact, we don't think that that's the case."
From Canada to India, one nation after another barred flights from Britain, while France banned British trucks for 48 hours while the strain is assessed.
British Prime Minister Boris Johnson on Saturday implemented strict lockdowns in London and large parts of southern England in response to rising coronavirus infections. He said the growth in cases appeared to be stemming from a new variant of the coronavirus that is about 70% more transmissible than existing strains.
Meanwhile, the European Union gave the go-ahead to the coronavirus vaccine developed by Pfizer and BioNTech, setting the stage for the first COVID-19 shots across the 27-nation bloc to begin on Dec. 27. The approval came just hours after the EU's drug regulatory agency said the vaccine meets safety and quality standards. It is already being dispensed in Britain and the U.S.