The United States on Wednesdayidentified its first known COVID case caused by the Omicronvariant, discovered in a fully vaccinated patient who traveledto South Africa, as scientists continue to study the risks thenew version could pose.
Public health officials said the infected person, who hadmild and improving symptoms, returned to the United States fromSouth Africa on November 22 and tested positive seven days later.
That patient was fully vaccinated but did not have a boostershot, according to Dr. Anthony Fauci, the top US infectiousdisease official, who briefed reporters at the White House.
Dr. Anthony Fauci speaks about the Omicron coronavirus variant case, which was detected in California, during a press briefing at the White House in Washington, US, on December 1, 2021.
The person is in self-quarantine and all of the patient'sclose contacts have tested negative, he said.
Key questions remain about the new variant, which mutated inways that health experts think could improve its ability to bothspread and evade some of the defenses provided by vaccines. Workis underway to update those vaccines, if necessary.
Omicron has been found in two dozen countries and territories, includingseveral in Europe plus Canada, Australia, Japan, China's Hong Kong andIsrael.
The United States has not yet detected communitytransmission of Omicron. Across much of the country, COVIDtransmission remains high but new cases have held fairly steadyover the last two weeks, according to a Reuters tally.Three-quarters of all COVID samples in South Africa are now Omicron.
"The critical thing is, over the next week or so, will wesee any community transmission from that case," said AndyPekosz, virologist at the Johns Hopkins Bloomberg School ofPublic Health. "That's a critical thing that we want to keep aneye on."
Pekosz said the variant could make the relatively new set ofantiviral pills from Merck and Pfizer moreimportant by helping to reduce the severity of infections.
Fauci said it could take two weeks or more to gain insightinto how easily the variant spreads from person to person, howsevere is the disease it causes and whether it can bypass theprotections provided by vaccines currently available.
The Biden administration has asked fully vaccinated peopleto seek booster shots after their initial doses. Sixty percentof Americans are fully vaccinated andabout a fifth of those people took boosters, according to theUS Centers for Disease Control and Prevention.
For days, US health officials have said the new variant– first detected in southern Africa and announced on November 25 – was likely already in the United States as dozens of othercountries also detected its presence.
AFP
Travelers wear protective face masks at Denver International Airport on November 30, 2021 in Denver, Colorado as concern grows worldwide over the Omicron coronavirus variant.
"This new variant is a cause for concern but not a cause forpanic," Biden said on Wednesday before the Omicron case wasannounced. A spokesperson, Jen Psaki, said he the president hadbeen briefed by his team on the first known US case.
Benchmark US stock indexes turned negative on the news.The S&P 500 fell by more than 1 percent, extending to nearly 4 percentits loss in price terms over the past week. The World HealthOrganization named the variant as one of concern on Friday.
The United States has barred nearly all foreigners who havebeen in one of eight southern African countries. On Tuesday, theCDC directed airlines to disclose names and other information of passengers who have been to thosecountries.
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