Wave-Like Spread of Ebola Zaire
(A) Human outbreak locations in Gabon and Congo as reported . Also shown are October 2003 human outbreak at Mbandza village and April 2004 ape die-off around Iboundji (Lokoué) Clearing in Odzala National Park. Yellow arrows represent epizootic path suggested by phylogenetic analyses.
(B) Sites of all primary outbreaks of Ebola Zaire in humans documented [2,14] and the epizootic path suggested by the spatio-temporal pattern of outbreaks (yellow arrows). Best fitting origin found through ML search for the spatial location that produced the strongest correlation between outbreak date and geographic distance from the origin. ML search based on the correlation between patristic genetic distance and spatial separation between outbreaks places the epizootic pivot point just southeast of Booué. In both figures, shading of circles is proportional to time after first outbreak in series.