JUNE 2015. BOZEMAN, MT

One year ago at this time, the Ebola outbreak in West Africa was just emerging from a lull, a falsely reassuring hiatus, like the “phony war” that settled over Europe in 1939, after Hitler’s invasion of Poland.  During early April, 2014, there was optimism among health officials that control measures were working--in Guinea, where it had all IMG 3061begun, and in the two other affected countries, Liberia and Sierra Leone; there was guarded confidence that those efforts would soon bring the outbreak to an end.  Some of the expert responders from overseas went home, to the CDC in Atlanta and elsewhere.  Then in late May came a disconcerting surge.  The incidence of new cases rose abruptly.  Traditional funeral practices and other factors allowed the virus to spread; response efforts, facilities, and supplies turned out to be insufficient.  Sick people were traveling—across borders among the three countries, and from the countryside to towns.  By mid-June, the disease had reached Liberia’s capital, Monrovia.  You know what happened next: Instead of an end, there was a geometrical getaway, an explosion of cases, as the outbreak became an epidemic.

As of yesterday, the official count from the World Health Organization is this: 27,237 cases and 11,158 deaths.

Furthermore, the epidemic still hasn’t ended—though it has fallen below the attention threshold for most news media outside of Africa.  Liberia is presently free of Ebola cases, but Guinea and Sierra Leone are not.  In fact, during two consecutive weeks now there have been slight increases in the new case counts for Guinea and Sierra Leone.  That unnerving little trend, plus the continuing occurrence of puzzling new cases for which the source (who infected whom?) can’t be identified, “highlights the challenges” (in the careful language of the WHO) of bringing this whole gruesome chain of events to a close.

Another unnerving fact is that there’s still so much about Ebola virus disease that we don’t understand.  At the top of that list of unknowns is the identity of the reservoir host—the creature in which the virus abides, quietly, inconspicuously, when it’s not causing devastation among humans.

IMG 3006Thirty-nine years have passed since the first recognized spillover of Ebola virus into people, and we still don’t know the answers to two crucial questions: 1) What is the reservoir host? and 2) Why has it been so hard, for so long, to answer question 1?

Last autumn, in the midst of the misery in West Africa and the feverish, confused worry about Ebola elsewhere, National Geographic asked me to look into this subject.  I was partnered with a talented young combat photographer, Pete Muller, a man with a serious heart and an artist’s eye, who works out of Nairobi.  We converged in Abidjan, Ivory Coast, to follow a team of Ebola researchers into the field.  Other journalist teams have done fine and heroic work in reporting the medical, human, and public-health aspects of the crisis.  This was a different sort of assignment.  We were investigating the ecology of Ebola.  The resulting story, in the July 2015 issue of National Geographic, can be read here.