Burial rituals allowed the virus to spread before alarms were raised, while testing missteps delayed detection, according to sources. Experts say delays could hurt efforts to stem the spread of the deadly illness, which has been declared a public health emergency of international concern.

A new Ebola outbreak in DRC went undetected for three weeks because field diagnostics couldn't identify the Bundibugyo strain. What the delay means for the response.

Ebola virus disease is among the world’s most deadly infectious illnesses, with outbreaks killing anywhere from a quarter to almost 90% of those who contract it

Ebola likely spread weeks before health officials knew about cases.

The Bundibugyo strain spread undetected for at least a few weeks, health experts and aid workers said