AILSA CHANG, HOST:
Ebola has been spreading for more than two months in the Democratic Republic of Congo, and health officials are not keeping up. The virus has killed almost 1,000 people and sickened more than 2,400. And most of these cases are not showing up on the radar of the World Health Organization. As NPR's Jonathan Lambert reports, that's making the response more difficult.
JONATHAN LAMBERT, BYLINE: In mid-May, the first Ebola cases were confirmed in Rwampara and Mongbwalu, two mining towns in the northeast. Since then, the outbreak has grown. Armand Sprecher is a physician with Doctors Without Borders. He's currently in DRC.
ARMAND SPRECHER: The outbreak is well spread. You can see that there are lots of dots on the map of varying sizes.
LAMBERT: The biggest dots, representing the most cases, are near where it was first identified, but there are lots of smaller dots spread out across five provinces and separated by hundreds of miles.
SPRECHER: That's a lot of territory.
LAMBERT: This scope makes it hard to know exactly where the virus is spreading.
SPRECHER: Our best way to know where the hidden virus is is to keep track of known exposures. So that is, we find a sick person and say, who was in contact with that sick person, right? Who took care of them? Who did their laundry? Who touched them? Or who went to a burial where somebody had died of this?
LAMBERT: Identifying those contacts, informing them of their exposure and keeping tabs on them is known as contact tracing. In theory, it should be able to flag where the virus is and where it could go next, and it could help exposed people get care faster if needed.
SPRECHER: It's labor-intensive, but if you can do it well, you've got a really good handle on the outbreak.
LAMBERT: But as of now, the WHO says they don't have a good handle on this outbreak. Eighty percent of new cases are popping up outside of known contacts, says Nahid Bhadelia.
NAHID BHADELIA: That is an alarm bell for me.
LAMBERT: She's an infectious disease physician at Boston University who treated Ebola patients during the West Africa outbreak of 2014.
BHADELIA: I remember a moment during my deployment in Sierra Leone where I was coming out of an Ebola treatment unit, and one of our epidemiologists sat there and said, you know, there's thousands of people that need to be contact-traced. And everybody in the room realized the gravity of that. And that's what I think is happening.
LAMBERT: That high number could stem from contact tracers missing some contacts of known cases. More contact tracers would help, and the WHO says that 21,000 community workers are currently being trained. But Bhadelia thinks the bigger issue is that there are whole chains of transmission that officials just don't know about until it's too late.
BHADELIA: Probably a lot more cases that we're missing, and this means people are presenting much later to care.
LAMBERT: Another problem is that many people just aren't able to or interested in coming to clinics. About two-thirds of deaths are occurring outside of the health system, according to the WHO. Boghuma Titanji is an infectious disease physician at Emory. She points to one major factor.
BOGHUMA TITANJI: Lots of mistrust towards the medical science and the people who are investigating the outbreak because there have been historical what is thought to be betrayals of those communities, which make them less likely to be trusting of contact tracers or people who are working to contain the outbreak.
LAMBERT: Regaining that trust is difficult work, but Bhadelia thinks recent developments could help.
BHADELIA: I think that you can build trust by providing better care, and that better care can, of course, be access to potentially promising treatments.
LAMBERT: There are no approved treatments for the kind of Ebola that's spreading, but clinical trials for two therapies as well as a drug that could prevent exposed people from getting sick are now underway. Bhadelia hopes that could attract more people to seek help. Ultimately, that's what's needed to help patients survive and control the outbreak. Jonathan Lambert, NPR News. Transcript provided by NPR, Copyright NPR.
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