White House Keeping an Eye on Two New Omicron Subvariants

Ralph Ellis

April 15, 2022

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The White House is paying close attention to BA.4 and BA.5, two new subvariants of the COVID-19 Omicron strain that are being tracked by the World Health Organization and have appeared in nations including South Africa, said Anthony Fauci, the president's chief medical adviser.

"We spoke to [South Africa] as recently as Sunday, that they can't make any statements right now about BA.4 or BA.5," he told Politico's Global Pulse newsletter, noting that it's not a surprise for a virus to mutate. "A phenotypic consequence may mean it makes it a little bit more or less transmissible."

The World Health Organization is analyzing the subvariants to find out how infectious and dangerous they might be. Reuters reported this week that health authorities had found a few dozen cases in South Africa, Denmark, Botswana, Scotland, England, Belgium, Denmark, and Germany.

At a Wednesday news conference, WHO lead epidemiologist Maria Van Kerkhove, PhD, said less than 200 sequences of BA.4 and BA.5 have been detected so far.

The infected people don't appear to be getting sicker than with other forms of Omicron, she said.

"We're tracking very closely trends in cases to see if there's any uptick in case detection in terms of incidents, but we haven't really seen any change in that epidemiology, we have not seen a change in severity," she said.

At the same news conference, Mike Ryan, MD, the executive director of the Health Emergencies Program for the WHO, warned that the coronavirus continues to evolve – meaning it could evade current vaccines – and health organizations need to keep tracking them.

"We simply cannot afford to lose sight of this virus," he said. "It would be very, very, very short-sighted to assume that lower numbers of cases means an absolute lower risk. We're very pleased … to see the deaths dropping, but this virus has surprised us before, this virus has caught us off guard before."

All versions of Omicron have proved to be highly transmissible. The BA.2 subvariant now represents about 94% of all sequenced cases but does not appear to cause severe disease, Reuters said. The CDC said BA.2 accounted for three-quarters of all COVID cases in the United States.


Global Pulse newsletter: "White House on the lookout for BA.4 and BA.5."

Reuters: "WHO says it is analysing two new Omicron COVID sub-variants."

World Health Organization: "COVID-19, Ukraine & Other Global Health Issues Virtual Press conference transcript – 13 April 2022."


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