Fauci warns new coronavirus variants are 'wake-up call,' says scientists must be ready to tweak vaccines

Dr. Anthony Fauci said the increasing spread of multiple coronavirus variants in the U.S. should serve as a "wake-up call," stressing the need for vaccine companies to be ready to make new versions of the shots as the country works to quickly vaccinate as many people as possible. 

The government’s top infectious disease expert made the comments Friday during a White House coronavirus briefing with the new U.S. Centers for Disease Control and Prevention director, who said the country "should be treating every case as if it's a variant."

Scientists have been closely following worrisome new variants circulating around the world, complicating efforts to combat the pandemic. These include the highly-contagious coronavirus variants first detected in the U.K., South Africa and Brazil — all three of which have been reported in the U.S.

In his remarks, Fauci discussed recent findings from vaccine makers Novavax and Johnson & Johnson and warned they were a "wake up call to all of us" as the virus continues to mutate. He said scientists will have to be "nimble to be able to adjust readily" to make tweaks to the vaccines if needed.

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Novavax said this week that its two-dose COVID-19 vaccine candidate appears to be 89% effective based on early findings from a British study. But it also found that the vaccine may not be as effective against the fast-spreading variant first detected in South Africa.

Johnson & Johnson, which has another long-awaited vaccine candidate, said Friday that its single-shot vaccine was found to be 66% effective overall at preventing moderate to severe illness, and much more protective — 85% — against the most serious symptoms. The vaccine was found to work better in the U.S. — 72% effective against moderate to severe COVID-19 – compared to 57% in South Africa, where it was up against an easier-to-spread mutated virus.

Fauci called the recent results overall "very encouraging," noting the fact that Johnson & Johnson’s vaccine is just one shot and easier to store. Both of the approved Pfizer and Moderna vaccines require two doses spaced apart and ultra-cold storage. But he said the findings further underscore the need to quickly vaccinate as many people as possible.

"The virus has a playing field, as it were, to mutate. If you stop that, and stop the replication, viruses cannot mutate if they don’t replicate," Fauci said. "That’s the reason to continue to do what we’re doing. Namely intensify our ability, and our implementation of, to vaccinate as many people as possible, as quickly as possible."

This week, the South African variant was detected in the U.S. for the first time, with two cases diagnosed in South Carolina, and the variant from Brazil was reported in a patient in Minnesota.

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CDC Director Dr. Rochelle Walensky, who began her role last week, said the U.K. variant had been confirmed in at least 379 cases in 29 states, as of Jan. 27. Walensky said public health officials remain concerned about the variants and "are rapidly ramping up surveillance and sequencing activities" to closely monitor and identify them.

Earlier this month, the CDC warned that the highly-transmissible U.K. variant, known as B.1.1.7, could become the dominant strain found in the U.S. and lead to a spike in cases and deaths, further straining the health care system.

"By the time someone has symptoms, gets a test, has a positive result and we get the sequence, our opportunity for doing real case control and contact tracing is largely gone," Walensky said during the briefing. "And so I think, and I believe, that we should be treating every case as if it's a variant during this pandemic right now."

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This story was reported from Cincinnati.