Editorial Outbreak of Ebola Virus Disease in Guinea: Where Ecology Meets Economy

Ebola virus is back, this time in West Africa, with over 350 cases and a 69% case fatality ratio at the time of this writing [1]. The culprit is the Zaire ebolavirus species, the most lethal Ebola virus known, with case fatality ratios up to 90%. The epicenter and site of first introduction is the region of Guéckédou in Guinea’s remote southeastern forest region, spilling over into various other regions of Guinea as well as to neighboring Liberia and Sierra Leone (Figure 1). News of this outbreak engenders three basic questions: (1) What in the world is Zaire ebolavirus doing in West Africa, far from its usual haunts in Central Africa? (2) Why Guinea, where no Ebola virus has ever been seen before? (3) Why now? We’ll have to wait for the outbreak to conclude and more data analysis to occur to answer these questions in detail, and even then we may never know, but some educated specula-tion may be illustrative. The Ebolavirus genus is comprised of five species, Zaire, Sudan, Taı ̈ Forest, Bundibugyo, and Reston, each associated with a consistent case fatality and more or less well-identified endemic area (Fig-ure 2). Zaire ebolavirus had been previ-ously found only in three Central Africa