Via Le Quotidien in Dakar: Ebola - Presence of a unit of MSF in Dakar: The Teranga refused to doctors. Excerpt from the Google translation:
To protect its population from the risk of contracting Ebola, Senegal has banned entry to its ground planes from Guinea Conakry, Sierra Leone and Liberia. This even extends to aircraft Doctors Without Borders who need to carry medical personnel in the affected areas. But not to be accused of refusing to participate in the effort to eradicate the disease, the Senegalese authorities have found a solution that sounds like a stopgap.
Evidently MSF's original plan was to use Dakar as a staging point for flights to Sierra Leone, Liberia, and Guinea, especially for bringing new people in and rotating others out. But Senegal, having banned flights from hot-zone countries, wouldn't agree.