Date Published: April 05, 2018
Publisher: The American Society of Tropical Medicine and Hygiene
Author(s): Linda M. Mobula, Nathalie MacDermott, Clive Hoggart, Kent Brantly, William Plyler, Jerry Brown, Bev Kauffeldt, Deborah Eisenhut, Lisa A. Cooper, John Fankhauser.
Although the high case fatality rate (CFR) associated with Ebola virus disease (EVD) is well documented, there are limited data on the actual modes of death. We conducted a retrospective, observational cohort study among patients with laboratory-confirmed EVD. The patients were all seen at the Eternal Love Winning Africa Ebola Treatment Unit in Monrovia, Liberia, from June to August 2014. Our primary objective was to describe the modes of death of our patients and to determine predictors of mortality. Data were available for 53 patients with laboratory-confirmed EVD, with a median age of 35 years. The most frequent presenting symptoms were weakness (91%), fever (81%), and diarrhea (78%). Visible hemorrhage was noted in 25% of the cases. The CFR was 79%. Odds of death were higher in patients with diarrhea (odds ratio = 26.1, P < 0.01). All patients with hemorrhagic signs died (P < 0.01). Among the 18 fatal cases for which clinical information was available, three distinct modes of death were observed: sudden death after a moderate disease process (44%), profuse hemorrhage (33%), and encephalopathy (22%). We found that these modes of death varied by age (P = 0.04), maximum temperature (P = 0.43), heart rate on admission (P = 0.04), time to death from symptom onset (P = 0.13), and duration of hospitalization (P = 0.04). Although further study is required, our findings provide a foundation for developing treatment strategies that factor in patients with specific disease phenotypes (which often require the use of aggressive hydration). These findings provide insights into underlying pathogenic mechanisms resulting in severe EVD and suggest direction for future research and development of effective treatment options.
The 2013–2016 West Africa Ebola virus disease (EVD) outbreak was unprecedented, given its duration, geographic scope, and high caseload of more than 28,600 reported cases and 11,300 deaths.1 In Monrovia, Liberia, faith-based organizations (Samaritan’s Purse and SIM) developed and operated the Eternal Love Winning Africa (ELWA-1 and 2) Ebola Treatment Units (ETUs) from June to August 2014, with the support of Medecins Sans Frontieres-Belgium (MSF-B).
The study protocol was approved by the Institutional Review Board at the University of Liberia and the Liberian Ministry of Health.
A stark finding from this small data set is the well-defined modes of death and clinical syndrome patients demonstrated in the 24 to 48 hours before death and the suggestion that these differed with age and duration of hospitalization, but not time from symptom onset to presentation at a treatment facility. There could be several reasons for this including a slightly different underlying pathogenesis or interaction between the immune system and virus at different ages. Genetic predisposition dictating immune response may be another possible explanation for the varied modes of death observed and is currently under investigation. Given the evidence for minimal viral sequence variation during the epidemic, varied pathogenicity of the infecting virus is unlikely.7,8