Predicting and Evaluating the Epidemic Trend of Ebola Virus Disease in the 2014-2015 Outbreak and the Effects of Intervention Measures

Guo, Zuiyuan; Xiao, Dan; Li, Dongli; Wang, Xiuhong; Wang, Yayu; Yan, Tiecheng; Wang, Zhiqi

A compartment transfer block diagram was constructed based on the transmission patterns and control measures of EVD (Fig 6B) . When a susceptible person in a free environment (S) comes in contact with a patient in a free environment (I), an un-decontaminated corpse of an EVD patient (D), or a recovering but still infectious patient (R), some people in S status become infected and enter the incubation period (E). People in E status can transfer to I or U status (suspected cases) to accept treatment and be isolated. Some people in the S block who are not infected, but present with EVD-like symptoms are transferred to the U block. Once a diagnosis is confirmed in suspected cases in the U block, these confirmed cases and some patients in the I block are both transferred to the P block (confirmed cases in isolation). Medical staff (H) are at high risk of infection due to close contact with people in the U and P blocks. Once an individual is confirmed to be in the I block, their close contacts are immediately monitored and isolated for observation (Q block). Some infected cases in the Q block are transferred to the P block after diagnosis. Uninfected cases return to the S status after the maximum incubation period.