The United States recorded its first confirmed Omicron variant case in San Francisco on Wednesday. The individual returned from South Africa on November 22 and reported mild symptoms, according to the U.S. Centers for Disease Control and Protection (CDC).

The individual had been fully vaccinated, with two doses of the Moderna vaccine, and has recovered from the symptoms.

That the first case was found in San Francisco is not a surprise to experts, as the city has been among the top in the country for sequencing positive tests throughout the pandemic.

Following the first reports from South Africa and Botswana of the variant last week, over 20 countries have detected new cases.

The discovery of the new variant coincides with an anticipated winter surge which the Biden administration has been prepping for.

In a call with reporters, senior White House officials said the administration will be targeting testing and boosters to help curb the spread of the virus.

The U.S. will now require stricter testing rules for all inbound travelers, regardless of citizenship or residency status, to include a mandatory negative test one day before departure to the U.S. In addition, insurers will be required to cover 100% the cost of at-home testing kits. Prior to this, consumers had been paying out of pocket for the kits, which range in price from $14 to more than $100. But details have yet to be ironed out.

The administration will also be launching family vaccination clinics, focusing on mobile and community health sites where all eligible ages in a family can be vaccinated at one time.

Vaccine efficacy

Meanwhile, vaccine makers announced efforts to begin work on a variant-specific shot.

Pfizer (PFE) CEO Albert Bourla and partner BioNTech (BNTX) CEO U?ur ?ahin both expressed confidence in their vaccine against Omicron, also known as B.1.1.529.

"I don't expect in any scenario to be that we don't protect at all. Actually, that's very, very unlikely," Bourla told Bloomberg this week.

Sahin similarly told Reuters he expects the vaccine to hold up and that his bigger worry is people who have not been vaccinated.

Moderna (MRNA) CEO Stéphane Bancel is less optimistic. He told the Financial Times that he expects the effectiveness of the vaccine to significantly drop.

"I think it’s going to be a material drop. I just don’t know how much because we need to wait for the data," he said.

Johnson & Johnson (JNJ) and Novavax (NVAX) have also announced plans to pursue a variant-specific shot.

However, some experts are wary of the rush to respond in light of scant data. In addition, the vaccines appear to still be able to protect against the worst effects of the virus.

Dr. Paul Offit, director of the Vaccine Education Center and attending physician in the Division of Infectious Diseases at Children’s Hospital of Philadelphia, told Yahoo Finance that the vaccines are likely to hold up against severe illness and prevent hospitalizations, even though the initial data was surprisingly good against milder infection.

"Where I think we got seduced ... was we had protected efficacy against mild symptoms of 95% (in Phase 3 data), and that was remarkably high. But remember that was three-month studies, that was not going to hold up in real life," Offit said.

He believes not enough attention is being paid to the long-term or durable protection from memory cells in the body. He and two former U.S. Food and Drug Administration heads penned an op-ed in the Washington Post to that effect.

Dr. Peter Hotez, Co-Director of the Center for Vaccine Development at Texas Children’s Hospital and Dean of the National School of Tropical Medicine at Baylor College of Medicine, believes that with three doses of mRNA, and two doses of the J&J vaccine, a person will likely have the right amount of protection against the new variant.

But Hotez is waiting on the data from CDC studies and real-world evidence from South Africa and other places.

"I always discount comments from pharma CEOs because that's for (the benefit of) shareholders," Hotez said.

Hotez thinks it's possible that both the Delta and Omicron variants could circulate simultaneously in the U.S. this winter.

Early clues about Omicron's impact have just begun to emerge this week. Reports from South Africa appear to indicate mild COVID-19 disease among the infected, and a report from Israel indicates the vaccines are holding up against the variant.

Offit believes that despite the alarming number of mutations in the variant, it could end up being more transmissible but cause less severe disease.

"If the virus becomes more contagious and less virulent, in many way that's what you want," he added.

Follow Anjalee on Twitter @AnjKhem

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