SAN FRANCISCO (CBS SF) -- A person who returned to the San Francisco Bay Area from a trip to South Africa has tested positive for the COVID omicron variant -- the first confirmed case in the United States.
Director of the National Institute of Allergy and Infectious Disease Dr. Anthony Fauci made the announcement Wednesday at the White House. The California and San Francisco Departments of Public Health and the US Centers for Disease Control and Prevention confirmed that the case was caused by the omicron variant through genomic sequencing conducted at the University of California at San Francisco, and confirmed with the CDC.
In a news release, San Francisco officials said the individual was a traveler who returned from South Africa to San Francisco International on November 22.
"The individual, who is a San Francisco resident, is self-isolating and is experiencing mild symptoms," the officials said. "We are continuing to speak with the individual about any persons with whom they have been in contact."
The individual, who was not named, fell ill and sought medical treatment that led to the discovery on Nov. 29.
"This is not a surprise," said Dr. Grant Colfax, the city's director of health at a news conference. "We knew that omicron was going to be here. We thought it was already here. We just hadn't detected it yet. This is a cause for concern but it also certainly not a cause for us to panic. We have been prepared in the city for this."
The individual had received a full dose of the Moderna vaccine but had not gotten a booster shot.
"San Francisco is well-positioned to respond to variants," Colfax said. "Our vaccine rate is high. More boosters are going into arms every day...Our masking and vaccine requirements are among the most stringent in the country...There is still a lot we don't know about omicron although there is a strong likelihood that it is more infectious delta."
"We don't know how sick it will make people," Colfax continued. "But that is being studied furiously and we don't know how fully effective the vaccines are in protecting against transmission or serious cases of illness or hospitalizations."
As for putting back in place any restrictions, Colfax said: "At this time, we do not anticipate changing any of our health orders or changing any current restrictions or imposing new restrictions on activity in San Francisco. We obviously are following these developments very closely. We will share additional information as we have it."
The strain was quickly identified in the UCSF lab of Dr. Charles Chiu, who joined Colfax at the news conference.
"This particular sample, I heard about it yesterday at about 3 p.m.," he said. "We were able to receive the sample in the laboratory by 8 p.m. We ran a very fast molecular test which looks for spike gene dropout. What this test can tell you that you may have detected omicron, but it's not conclusive."
"We were able to get the results of that test in two hours showing that potentially this was an omicron variant sample, but to confirm this finding we needed to sequence the genome...We able to confirm the detection of omicron in five hours and had nearly the entire genome in eight hours. At 4 a.m. last night we were able to conclusively demonstrate that this was an infection of the omicron variant."
Gov. Gavin Newson, speaking at a news conference to encourage vaccinations, said state health officials were "learning in real time" about what dangers the omicron strain presents.
"The longer we live with this virus, the more mutations, the more variants we will see," he said. "That's why we have to face down the skepticism, face down the misinformation, face down the disinformation around the safety and efficacy of these vaccines."
The World Health Organization designates omicron a "variant of concern." In a technical brief released this week, WHO noted that the variant poses a "very high" global risk. The variant was first identified by scientists in South Africa, and has since been detected in several countries.
Scientists are working to determine how transmissible the variant is, how sick it makes people and how well current vaccines work against it. Until more information is learned about the variant, the United States restricted travel from South Africa and seven other countries.
On Monday, President Joe Biden called the variant "a cause for concern, not a cause for panic," saying "we'll have to face this new threat just as we face those who have come before it."
Health officials are urging people to get vaccinated against Covid-19, or get a booster if they're eligible. Other measures such as masks, handwashing, physical distancing, and ventilation will still work against the omicron variant.
The delta variant of the coronavirus remains the dominant variant globally and in the United States.
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