Fig. 2

Impact of interventions in Pujehun district. The probability of eliminating an otherwise large outbreak is defined as 1–p _i /p _ni , where p _i and p _ni are the probabilities of outbreak with and without intervention [19]. (a) Net reproduction number over time. (b) Probability of disease elimination in Pujehun district by assuming isolation of cases and by varying the number of Ebola virus disease (EVD) beds and the average time from symptom onset to hospitalization in the absence of other interventions (e.g. safe burials for unhospitalized cases and contact tracing). Probability of hospitalization set to 90 %. (c) Probability of disease elimination in Pujehun district by assuming isolation of cases and by varying the number of EVD beds and the probability of hospitalization in the absence of other interventions (safe burials for unhospitalized cases and contact tracing). The average time from symptom onset to hospitalization is set to 4 days. (d) Probability of disease elimination in Pujehun district by assuming isolation of cases and contact investigation and by varying the contact tracing levels (with respect to observed values in Pujehun district) and the number of EVD beds. Contact tracing level is defined as the percentage of cases detected and isolated through contact investigation, namely 30 % in July 2014, 40 % in August, and 60 % in September. The average time from symptom onset to hospitalization is set to 4 days and the probability of hospitalization is set to 90 %. (e) Probability of disease elimination in Pujehun district by assuming isolation of cases and contact investigation and by varying the timing of implementation of contact investigation and the number of EVD beds. The contact tracing level is set to values observed in Pujehun district, namely 30 % in July, 40 % in August, and 60 % in September 2014. The average time from symptom onset to hospitalization is set to 4 days and the probability of hospitalization is set to 90 %