Clinical Sequelae and Urogenital Viral Dynamics in Survivors of Ebola Virus Disease

项目总结

PROJECT SUMMARY The Ebola epidemic that has devastated West Africa evolved within months from a regional humanitarian crisis to a global public health emergency. Over 27,000 infections and more than 11,000 deaths were reported by the World Health Organization (WHO) – an underestimate that already eclipses the numbers of infections and deaths in all previous Ebola outbreaks combined by orders of magnitude. While this epidemic has ebbed, and may even be over, the clinical complications of Ebola virus disease (EVD) endure for the majority of the thousands of survivors. Our work and that of others indicate that musculoskeletal, neurologic, and ocular complications can persist even two years after recovery from acute Ebola disease. Further, there is evidence that there can be sustained shedding of at least viral RNA in semen and vaginal fluid of survivors, which could signal presence of infectious virus and/or serve to stimulate immune responses that may produce certain post-Ebola symptoms. The small size of previous outbreaks and the absence of adequate infrastructure to collect, process and analyze samples in the field have limited our understanding of the natural history of Ebola survivorship. The primary goal of this proposal is a better understanding of the clinical sequelae of EVD. Specifically:  In AIM I we will describe and categorize the clinical symptomatology of Ebola survivors and investigate host- and disease-related factors for these conditions.  In AIM II we probe putative pathogenic mechanisms for post-Ebola conditions including sustained immune activation, altered gut integrity, and persistence of viral antigens in the uro-genital compartment. We will conduct this work in the context of close and strong working relationships with health care leaders and Ebola survivor representatives in West Africa, and a well-developed infrastructure for clinical research we have established in Liberia and Sierra Leone where we have recruited, enrolled, and longitudinally followed and sampled over 400 Ebola survivors. Establishment of these cohorts allowed our team to determine the feasibility of our approach and develop, pilot, and refine the procedures needed to sustain high-quality data collection. This work also allows us to build and support capacity. Staff in both nations have been trained in research methodology and are being encouraged to develop their own proposals. We have established a validated platform for Ebola RNA detection in blood, semen, and vaginal fluid at a national reference lab in Liberia and have trained this site in quality control. Collectively, the proposed work will provide a much-needed characterization of the convalescence from Ebola and its potential mechanisms, as well as better characterize the patterns of Ebola RNA detection in genital fluids. With 25 outbreaks over the past 40 years and a notable increase in the frequency of EVD outbreaks, the question is not if another outbreak will occur but when. This study will ensure that the world is better prepared for the next epidemic through the improved understanding of the clinical complications of Ebola virus disease, and through the implementation of clinical research platforms in areas that are likely to see a recurrence of EVD.