AMNA NAWAZ: Health officials are racing to contain a rapidly expanding outbreak of a rare strain of Ebola in Central Africa.

The World Health Organization declared an international public health emergency over the weekend.

So far, at least 116 suspected deaths and more than 300 other cases have been reported in the Democratic Republic of Congo and neighboring Uganda.

Today, the CDC confirmed at least one American has contracted the disease, a medical missionary who had been working in a hospital in the DRC.

That country's health minister pleaded with residents to visit new government treatment centers if they had symptoms.

DR.

SAMUEL ROGER KAMBA, Democratic Republic of the Congo (through translator): This is not a mystical disease.

Make yourself known.

Make yourself known so that you can be taken care of and so that we can prevent the disease from spreading.

AMNA NAWAZ: For more, we're joined now by Dr.

Craig Spencer.

He's an associate professor of public health and emergency medicine at Brown University.

He also contracted Ebola himself while working as a physician in West Africa during a 2014 outbreak.

Dr.

Spencer, welcome back to the "News Hour."

Thanks for joining us.

DR.

CRAIG SPENCER, Brown University School of Public Health: Thank you for having me on to talk about this.

AMNA NAWAZ: So, on top of all this other news today, the U.S.

announced an entry ban for noncitizens who've been in the DRC, Uganda or South Sudan in the last three weeks.

Let me just ask you, what concerns you most about this outbreak given what we know right now?

DR.

CRAIG SPENCER: What concerns me most is that we learned way too much, way too quickly for this to be anything but really bad.

I am concerned about the next few weeks or the next few months.

We have found ourselves weeks, maybe months behind when this first started spreading.

Over the last year, we have lost a lot of the response capacity, particularly here in the U.S.

And I'm also concerned about the fact that this is in a really tough region, not just because of this outbreak, not just because it's at a border, but because it's a place with a lot of conflict with mobile populations.

This would be a hard outbreak to manage in an ideal situation.

This is absolutely not the ideal situation.

AMNA NAWAZ: OK, let's take some of those piece by piece here, because the timeline of this, it's now believed the very first suspected case was about three weeks ago, a man who died in late April in DRC.

What is it about this strain or about the circumstances that took so long for us to know what was going on?

DR.

CRAIG SPENCER: Well, I will posit that the first case was likely well before that.

I say that because you don't go from one case a few weeks ago to hundreds and hundreds of cases this quickly.

So I think this has been spreading a lot longer.

And as we get genomic analysis, we're going to be able to get a better idea of how long this has been going on.

But your question stands, why did it take so long for us to recognize this?

I think part of it is that this health zone, the health zones that are impacted have limited health infrastructure.

They are plagued by a lot of conflict and instability.

It's a place that I have worked a lot in the last 15 years.

It's a place that is really difficult to provide health care, to get around.

And I also think that there were delays at the testing level, particularly because this Bundibugyo strain is different than the majority of outbreaks in the past that have been caused by either the Zaire strain or the Sudan strain, which are much more common causes of Ebola outbreaks.

AMNA NAWAZ: Tell us more about what we know about this strain, the Bundibugyo strain, as you mentioned.

Do we know enough to know how the response should be different?

DR.

CRAIG SPENCER: For all intents and purposes, primarily from the health care side, this is exactly like and the management is very much the same as any other type of Ebola.

There's only been two other Bundibugyo outbreaks.

This is already the largest., in fact, this is one of the larger Ebola outbreaks in history after the 2014 outbreak and a 2018 outbreak in the same area in D.R.

Congo where there's currently an outbreak.

What's different about this strain is that, unlike the Zaire strain that caused the 2014 outbreak that I was infected with, we don't have FDA-approved treatments for Bundibugyo.

We do for Zaire.

We have vaccines.

We have treatments that can help drive down the death rate.

But, for this strain, we have no investigational, no approved vaccines, no approved treatments, which means that responding to and controlling this outbreak is going to require good epidemiology, good contact tracing and good bread-and-butter public health, which, again, is going to be really difficult in a place that is plagued by conflict, that has a lack of good health infrastructure and providers, and is quite suspicious of outsiders.

AMNA NAWAZ: I just want to give folks a sense of what it's like for people on the ground who are experiencing this, the sense of fear, because people in the DRC and the neighboring area are really frightened right now.

This is a man named Franck Amani, who's from the Eastern city of Goma, sharing what it's like.

FRANCK AMANI, Resident of Goma, Democratic Republic of Congo (through translator): I'm very scared because we have heard about Ebola in previous years.

And now we're hearing that Ebola is in Goma.

I'm calling on the local authorities to intervene because we're also scared because of the war and now because of Ebola., We're really scared.

AMNA NAWAZ: Dr.

Spencer, you have worked on the ground in DRC, in this region in particular.

Do they have what they need to respond to this?

DR.

CRAIG SPENCER: Absolutely not, no.

I don't think anyone in Congo would tell you that they do either.

Look, this was a region that was already a really tough spot to work before last year, when the U.S.

cut a lot of its support to USAID and other NGO partners that were working in the region, not only for health care, but for a whole host of other humanitarian support.

I have been told that there's not sufficient personal protective equipment.

I know, from working in many of these clinics, that there's not the basics like gloves or in some places even running water, which can be helpful in preventing transmission.

And, as you mentioned, this is a place that has been plagued by a lot of instability for decades.

We have already seen how that's - - that has contributed here to a lot of movement around the region.

We also know that there are cases in Goma, which is a very large city.

It's also a big connection point to other places throughout Congo.

And we have seen cases unrelated to each other in Kampala, the most populous city in Uganda, hundreds of kilometers away, all of which makes me realize, one, this is going to get a lot worse before it gets better, and two, we still don't have a full handle on what exactly we're grappling with yet.

AMNA NAWAZ: In the 30 seconds or so we have left, what do you want to see the U.S., other international actors doing right now?

DR.

CRAIG SPENCER: We need to surge, not just because we're worried that there will be more Americans infected or that it will get on a plane, but because this outbreak is already big.

Over the last year, anti-American sentiment has surged because of the way that we pulled out our support overnight.

We need to fully engage our CDC.

We need to get back on the ground, make sure that U.S.

support, financial, logistical, and medical support, can help end this outbreak before it gets worse.

Otherwise, it's going to be a problem, not just for the region, but for the rest of the world.

AMNA NAWAZ: Dr.

Craig Spencer with Brown University, thank you so much for your time.

DR.

CRAIG SPENCER: Thank you.