There were still five questions pending, he said, and he began to list them: (1) Why were only half of the members of each household affected? (2) Why were so few hospital workers affected, compared to other Ebola outbreaks? (3) Why did the disease strike so spottily within the Bundibugyo district, hitting some villages but not others? (4) Was the infection transmitted by sexual contact? After those four he paused, momentarily unable to recall his fifth pending question. “The reservoir?” I suggested. Yes, that’s it, he said: What’s the reservoir?
