Key data for outbreak evaluation: building on the Ebola experience

Cori, Anne; Donnelly, Christl A.; Dorigatti, Ilaria; Ferguson, Neil M.; Fraser, Christophe; Garske, Tini; Jombart, Thibaut; Nedjati-Gilani, Gemma; Nouvellet, Pierre; Riley, Steven; Van Kerkhove, Maria D.; Mills, Harriet L.; Blake, Isobel M.

Despite the unprecedented scale of the 2013-2016 West African Ebola epidemic [1, 2] , detailed data were collected during the outbreak, which proved invaluable in guiding the response [3] [4] [5] [6] [7] [8] [9] [10] . Multiple studies have already considered the lessons to be learned from the Ebola experience with respect to coordinating international responses to health crises, strengthening local health systems and improving clinical care and surveillance tools [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] . Here we discuss what can be learned to improve real-time epidemiological assessment in future outbreaks via improved data collection and analyses, building on similar contributions after other epidemics [24 -26] . We focus on efforts to reduce and interrupt transmission. First, we outline analyses that are essential to inform response activities during different stages of an epidemic. Second, we detail the various types of data needed to perform these analyses, with examples from the Ebola experience. Third, we summarize the successes and challenges of data collection experienced during this outbreak, and the implications this had for answering key public health questions. Fourth, we suggest improvements that could be implemented in future outbreaks, again drawing from the Ebola experience. Finally, we discuss issues related to availability of data and analyses (box 1).