AILSA CHANG, HOST:
The Ebola outbreak that's raging in Africa could rival or even surpass the worst Ebola outbreak on record. That is according to a new analysis from the U.S. Centers for Disease Control and Prevention. NPR health correspondent Rob Stein joins us now. Hi, Rob.
ROB STEIN, BYLINE: Hey there, Ailsa.
CHANG: OK, so this sounds really grim. What is the CDC saying here, exactly?
STEIN: Yeah, this is pretty sobering. As you know, the Democratic Republic of Congo and Uganda are racing to contain this big outbreak of Ebola that prompted the World Health Organization to declare an international health emergency. So the CDC ran a number of scenarios to try to project just how bad it could get. And here's what Jason Asher from the CDC's Center for Forecasting and Outbreak Analytics told reporters at a late afternoon briefing where the analyses were released.
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JASON ASHER: If only 20% of cases enter isolation within two days of symptom onset, more than 20,000 cases are projected in 2 out of 3 of our scenarios.
STEIN: So, Ailsa, that's pretty explosive growth...
CHANG: Yeah.
STEIN: ...With 20,000 cases in just the next three months.
CHANG: Wow.
STEIN: And if the outbreak continues beyond that, the numbers could obviously climb higher, potentially much higher, which would make this the worst Ebola outbreak on record. About 28,000 cases occurred in the Ebola outbreak in West Africa that began in 2014. That was the largest on record, and the international response to this outbreak got off to a slow start.
CHANG: And this scenario that we're talking about, it's assuming that only 20% of people who get Ebola in this outbreak are isolated - right? - in order to keep them...
STEIN: Yeah.
CHANG: ...From spreading the virus. But is that isolation actually what is happening on the ground right now? Do we know?
STEIN: Yeah. You know, Ailsa, it's a very tough situation. The outbreak is happening in places where it's hard to get good information. But the CDC says they think that's probably on target for what's going on right now, given the difficult conditions. But the agency says isolating infected people and tracing their contacts is the key. And if international efforts can increase that isolation number, the scale of the outbreak could be far lower. Here's Asher again.
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ASHER: If 70% of cases started isolating within that two-day period, there is a 94% probability of limiting the outbreak to fewer than 10,000 cases.
STEIN: Again, that would be in just the next three months, so that's not a great scenario either.
CHANG: No.
STEIN: But it's obviously much better than the worst-case scenario...
CHANG: Right.
STEIN: ...Which is why so many alarm bells are going off around the world about this, you know, to limit the devastation in Africa and, of course, to help protect the rest of the world.
CHANG: Of course, because whenever there is an outbreak of Ebola anywhere, the disease could pose a threat to other countries. Did the CDC say anything about the possible threat to the U.S.?
STEIN: Yes. One of the three analyses released today specifically addresses the risk to the U.S., and it concludes the risk to the U.S. remains low. That's because while Ebola is a very dangerous disease, it doesn't spread nearly as easily as, say, COVID or the flu, and the U.S. has the capability to quickly identify cases, isolate people and trace their contacts. Here's Dr. Satish Pillai from the CDC.
SATISH PILLAI: The domestic risk remains low for the general U.S. population.
STEIN: So the CDC says there's no reason anyone should change their behavior or even worry about traveling internationally, other than, of course, to the Democratic Republic of Congo or Uganda.
CHANG: Right. That is NPR's Rob Stein. Thank you, Rob.
STEIN: You're welcome, Ailsa, anytime.
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