Telling stories with data

Ebola outbreaks before 2014

We all have vivid memory of the last Ebola outbreak.
By looking at the 33 previous events since 1976, what can we learn to understand this event and formulate ideas to prevent future outbreaks?
The most impacted countries before 2014 were DRC, Gabon, Sudan and Uganda (natural reservoirs of the virus hosts)
The virus subtype linked to the most outbreaks and cases/deaths in the past is the Zaire virus. This can be tied to the recent tragic outbreak in West Africa also due to a Zaire virus subtype.
The severity of the last outbreak in a different area of Africa brings a few questions to mind. Is the reservoir of virus hosts moving/expanding? Is the severity due to an increased virulence of the Zaire subtype or to a delayed emergency response.
Done using Altair and Vega-Lite with data from HDX.