The key to ending any infectious disease outbreak, especially one for which there's no approved vaccine, like the ongoing Ebola outbreak in the Democratic Republic of Congo, is getting slightly ahead of the virus.To do that, health officials need to quickly identify the possible routes a virus might spread, a practice known as contact tracing, says Armand Sprecher, an infectious diseases physician with Doctors Without Borders."We find a sick person and say, 'Who was in contact with that sick person? Who took care of them? Who did their laundry, who touched them? Or who went to a burial where somebody had died of this?'" he says.Spread by bodily fluids, the virus can only travel to these contacts.Identifying them all quickly, informing them of their exposure and keeping tabs on them can help prevent them from spreading the virus to others and get care faster if they develop symptoms.
"It's labor-intensive, but if you can do it well, you've got a really good handle on the outbreak," says Sprecher.Health officials do not have a good handle on the current outbreak.Just over two months in, nearly 1,000 people have died, and more than 2,400 people have been sickened by the virus.Daily case counts show no signs of slowing down.
Perhaps most concerningly, more than 80% of new cases are popping up outside of known contacts."That is an alarm bell for me," says Nahid Bhadelia, an infectious disease physician at Boston University who has worked on previous Ebola responses."It means that a lot more people have this disease than we think, and contact tracing is not keeping up."That high percentage could stem from the inability to trace all contacts of cases, giving them only a partial view of known transmission chains.The outbreak is centered in a region with a lot of transient workers and ongoing conflict, which can make it difficult to track down everyone who comes into contact with a known case.
More contact tracers would help, and the World Health Organization (WHO) announ...