Prognostic Analysis of Patients with Ebola Virus Disease

Background: The Ebola virus causes an acute, serious illness which is often fatal if untreated. However, factors affecting the survival of the disease remain unclear. Here, we investigated the prognostic factors of Ebola virus disease (EVD) through various statistical models. Methodology/Principal Findings: Sixty three laboratory-confirmed EVD patients with relatively complete clinical profiles were included in the study. All the patients were recruited at Jui Government Hospital, Sierra Leone between October 1st, 2014 and January 18th, 2015. We first investigated whether a single clinical presentation would be correlated with the survival of EVD. Log-rank test demonstrated that patients with viral load higher than 106 copies/ml presented significantly shorter survival time than those whose viral load were lower than 106 copies/ml (P = 0.005). Also, using Pearson chi-square test, we identified that chest pain, coma, and viral load (>106 copies/ml) were significantly associated with poor survival of EVD patients. Furthermore, we evaluated the effect of multiple variables on the survival of EVD by Cox proportional hazards model. Interestingly, results revealed that patient’s age, symptom of confusion, and viral load were the significantly associated with the survival of EVD cases (P = 0.017, P = 0.002, and P = 0.027, respectively). Conclusions/Significance: These results suggest that age, chest pain, coma, confusion and viral load are associated with the prognosis of EVD, in which viral load could be one of the most important factors for the survival of the disease. Author Summary: The current outbreak of Ebola virus disease (EVD) in West Africa is the largest and most complex Ebola outbreak since the virus was first discovered in 1976. Factors affecting the survival of the disease remain unclear. Here, we investigated the prognostic factors of EBV from 63 cases with relatively complete clinical profiles in Sierra Leone. Using different statistical models, we found that age, chest pain, coma, confusion and viral load were associated with the prognosis of EVD, in which viral load could be one of the most important factors for the survival of the disease.