Fauci: 'Need to assume' UK variant is more deadly

"We need to assume now that what has been circulating dominantly in the UK does have a certain degree of increase in what we call virulence - namely the power of the virus to cause more damage, including death," Fauci told CBS's Face The Nation.

Fauci, who is President Joe Biden's top COVID-19 medical adviser, said he was somewhat more worried about a separate variant from South Africa, although it has not yet been identified among U.S. cases of the novel coronavirus.

Reuters reported exclusively on Sunday that Biden will impose a ban on most non-U.S. citizens entering the country who have recently been in South Africa starting Saturday in a bid to contain the spread of a new variant of COVID-19, according to a senior U.S. public health official.

Video Transcript

ANTHONY FAUCI: We need to assume now that what has been circulating dominantly in the UK does have a certain degree of increase in what we call virulence-- namely the power of the virus to cause more damage, including death.

When you look at the effect of the change-- this lineage that is the UK lineage that is now in at least 20 states in the United States, the vaccine-induced antibodies, namely the vaccines that some of us have gotten and that we're rolling out-- Moderna and Pfizer vaccines seem to continue to be protective against the mutant strain. There's a very minor diminution. But the cushion that you have of efficacy is so large that it's not going to negatively impact.

A little bit more concerning with the South African islet-- namely the mutant that is now prevalent in South Africa, particularly its negative impact on some of the monoclonal antibodies that have been given for treatment, that it in some respects knocks out their efficacy. It looks like it does diminish more so the efficacy of the vaccine. But we're still within that cushion level of the vaccines being efficacious against these mutants.

Down the pike-- down the line, we may need to modify and upgrade the vaccines. We don't need to do that right now. The best way to prevent the further evolution of these mutants is to vaccinate as many people as possible with the vaccines that we have currently available to us.

- OK.

ANTHONY FAUCI: That's the best protection against this evolution.