Author Profile

Shannon M. Fast

Affiliation: Software and Algorithms, Draper Laboratory, Cambridge, Massachusetts, USA

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The Role of Social Mobilization in Controlling Ebola Virus in Lofa County, Liberia

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In Scenario 1 and Scenario 2, the capacity of the Lofa County ETUs was increased, as actually occurred, but no behavior change took place in the population. Scenario 1 fit the weekly case counts in June and July and extrapolated the trend to future months. Scenario 1 substantially overestimated the size of the outbreak, predicting 8585 or more reported cases by October 21 in 50% of simulations. Scenario 2 fit the weekly cases for June through October. A poor fit to the observed cases was obtained. Scenario 3 took into account gradually increasing awareness of EVD in the community, in addition to the expansion of the Lofa County ETUs, achieving an excellent fit to the observed weekly cases.

The West Africa Ebola virus epidemic now appears to be coming to an end. In the proposed model, we simulate changes in population behavior that help to explain the observed transmission dynamics. We introduce an EVD transmission model accompanied by a model of social mobilization. The model was fit to Lofa County, Liberia through October 2014, using weekly counts of new cases reported by the US CDC. In simulation studies, we analyze the dynamics of the disease transmission with and without population behavior change, given the availability of beds in Ebola treatment units (ETUs) estimated from observed data. Only the model scenario that included individuals’ behavioral change achieved a good fit to the observed case counts. Although the capacity of the Lofa County ETUs greatly increased in mid-August, our simulations show that the expansion was insufficient to alone control the outbreak. Modeling the entire outbreak without considering behavior change fit the data poorly, and extrapolating from early data without taking behavioral changes into account led to a prediction of exponential outbreak growth, contrary to the observed decline.  Education and awareness-induced behavior change in the population was instrumental in curtailing the Ebola outbreak in Lofa County and is likely playing an important role in stopping the West Africa epidemic altogether.