The threat posed by the Ebola outbreak in the Democratic Republic of Congo has intensified, with the confirmation that it is caused by the Bundibugyo species of the virus, for which there are no approved vaccines or antiviral therapies. At the same time, the high positivity rate, with eight laboratory confirmed cases out of 13 samples collected in various areas, and more reports of suspected cases and clusters of deaths, all point to a potentially much larger outbreak than currently is being detected and reported.