Figure 5. Large-scale geographic spread of RVFV in Africa and Saudi Arabia based on the S segment.

The directed lines connect the sources and target localities (shown by arrows) of viral lineages. The distinct introductions into Senegal and Mauritania were represented by different colors. The estimated time to the most recent common ancestor of strains from different countries are shown within rectangles and could be interpreted as the oldest possible year of introduction of that lineage at that locality.