Abstract：The basic reproductive number is the most important parameter for measuring epidemic potential and assessing the disease spreading risk. To assess the 2013 Ebola virus spreading risk, a modified least squares method is used to fit the data to give a more self-consistent theoretical basis. Very early Ebola epidemic data sets from the three hardest hit countries in West Africa (Guinea, Sierra Leone and Liberia) are fit to calculate the basic reproductive number with the results in good agreement with the actual spread. A risk evaluation model which uses an extended susceptible, exposed, infectious, and removed (SEIR) model based on the multi-epidemic hypothesis gives better predictions than the uniformly mixed assumption based SEIR model used in previous studies. The model and fitting method can help predict virus propagation, assess the effects of control measures, and predict the future trends of the epidemic spread to enable better containment of future epidemics.
马勋, 倪顺江, 申世飞. 基于早期监测病例的埃博拉病毒传播风险评估[J]. 清华大学学报（自然科学版）, 2017, 57(8): 821-825.
MA Xun, NI Shunjiang, SHEN Shifei. Risk evaluation of Ebola spreading based on early reported cases. Journal of Tsinghua University(Science and Technology), 2017, 57(8): 821-825.
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2017, Vol. 57 
