SCOTT SIMON, HOST:
A new coronavirus variant has been identified in several countries in southern Africa. The World Health Organization has designated it a variant of concern and given it the Greek letter omicron. Many countries, including the U.S., will start to restrict travel from South Africa and other countries in the region.
NPR health correspondent Rhitu Chatterjee joins us now. Thanks for being with us.
RHITU CHATTERJEE, BYLINE: Hi, Scott.
SIMON: What have scientists discovered at this point about omicron that has them so openly worried?
CHATTERJEE: So it's still early days, but there are several red flags. One, the variant's detection coincided with a steep increase in cases in South Africa. And in just less than two weeks, it's dominating all infections there. About 75% of cases are now caused by omicron. And preliminary evidence suggests it also has a higher risk of reinfection. So if you've got an infected once, the chances that you might be infected again may be higher with this one. So the WHO says the variant may have some advantages over other variants.
SIMON: And as you said, South Africa seems to have been hit early by the new variant. But as well, it has been detected in other countries, hasn't it?
CHATTERJEE: That's right. And I should add that the CDC put out a statement last night saying that this variant hasn't been detected in the U.S. yet. But it's already been found in Botswana, Israel, Belgium and Hong Kong. And scientists have been looking closely at omicron's mutations to understand why it's spreading so fast. The WHO's Dr. Maria Van Kerkhove spoke at a press conference yesterday.
(SOUNDBITE OF PRESS CONFERENCE)
MARIA VAN KERKHOVE: This variant has a large number of mutations, and some of these mutations have some worrying characteristics.
CHATTERJEE: So some mutations that the variant has can make it more contagious. Some can make the virus more effective at infecting cells. But what we don't know yet is how all those mutations work together to change, say, how the virus is spreading, how sick it can make you if you get infected, and very importantly, how it interacts with vaccines. And top scientists in the world are taking it very seriously and trying to answer those questions.
SIMON: What does the World Health Organization suggest that countries do in the meantime?
CHATTERJEE: So they're asking countries to amp up surveillance of the virus so we can have a better picture of where the variant is, how it's behaving. It's asking countries to do more testing. The variant can be detected using the currently available PCR test, which is good. It's also asking countries to share data with the agency, as well as with each other, through publicly available databases so scientists worldwide can study it and so we can get - more quickly get a handle on the variant. The WHO's Dr. Van Kerkhove reminded individuals that existing public health measures remain important for preventing the virus' spread and also to keep new variants from emerging.
(SOUNDBITE OF PRESS CONFERENCE)
VAN KERKHOVE: What's really important as an individual is to lower your exposure. These proven public health measures have never been more important - distancing, wearing of a mask, making sure that it's over your nose and mouth with clean hands, making sure you avoid crowded spaces. Be in rooms where there's good ventilation.
CHATTERJEE: And, of course, getting vaccinated because we know vaccines work well against delta, which is still the predominant variant worldwide.
SIMON: NPR's health correspondent Rhitu Chatterjee - thanks so much for being with us.
CHATTERJEE: Thanks, Scott. Transcript provided by NPR, Copyright NPR.