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In any infectious disease outbreak, testing is key to understanding the scope of the problem and to reining it in. Lack of testing was part of the reason the current Ebola outbreak in central Africa grew so large before officials raised alarm bells. As NPR's Jonathan Lambert reports, the situation has improved since then, but many cases are still going undiagnosed.
JONATHAN LAMBERT, BYLINE: Health officials in the Democratic Republic of Congo began worrying about possible Ebola cases in mid-April. Deaths that seemed suspicious spurred health officials to take samples and send them to the nearest lab in Bunia.
JEAN-JACQUES MUYEMBE: The first samples were tested on April 30 in Bunia.
LAMBERT: That's Jean-Jacques Muyembe. He heads the DRC's national biomedical research lab and helped build up the country's extensive testing infrastructure. He says those initial samples turned back negative. So did samples sent a couple weeks later. Samples then had to be sent to the main lab in Kinshasa, hundreds of miles away.
MUYEMBE: They were positive for Ebola Bundibugyo.
LAMBERT: It turns out the original lab in Bunia was using a machine that couldn't detect the Ebola species that was actually circulating called Bundibugyo. That several weekslong delay allowed the outbreak to grow. People who might've isolated after getting a positive test instead spread the virus to others. Suspected cases ballooned as labs struggled to keep up with incoming samples. Now, it's a different situation, says Abdi Mahamud, the director of health emergency alert and response at the World Health Organization.
ABDI MAHAMUD: The diagnostic capacity has improved significantly from where we were 3 1/2 weeks ago.
LAMBERT: There are now seven laboratories in eastern DRC that can process Bundibugyo samples, mostly with a new machine called RADI-One. Some of those labs can process a hundred samples a day on-site rather than having to ship samples to Kinshasa. The major backlog is mostly gone, but Mahamud worries about the ability to keep up as cases climb.
MAHAMUD: We're very much aware we are still behind the curve. So if transmission continues, both geographically or the case load increases, we will require additional surge and more stuff.
LAMBERT: That stuff is primarily machines that can automate testing like RADI-One. There just aren't enough, he says, and WHO is in talks with manufacturers to boost production. Even if that happens, lab testing has other limitations. Caia Dominicus is the senior technical adviser at the International Pandemic Preparedness Secretariat, a nonprofit.
CAIA DOMINICUS: Sample transport is a very serious bottleneck.
LAMBERT: It can take days for samples to reach a lab. Some areas are almost completely inaccessible, she says, from lack of roads or ongoing conflict.
DOMINICUS: It really makes the logistics and the community engagement much, much harder. So it - that really complicates kind of the diagnostic response as well.
LAMBERT: Rapid tests, like the ones that became widely used during COVID, could improve that response. You can just take a pinprick of blood and get a result in minutes.
DOMINICUS: And that's really what lets you make an isolation or a contact-tracing decision on the spot, rather than having to wait hours or days, which can really delay the overall response.
LAMBERT: Right now, there are no rapid tests approved for Bundibugyo, but there are tests for other Ebola species that could work. Making sure they do or developing new ones will take potentially weeks to several months, but researchers say that time could be worth it. The sooner someone knows they're positive, the sooner they can isolate to stop the spread.
Jonathan Lambert, NPR News. Transcript provided by NPR, Copyright NPR.
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