Ebola and Marburg

Marburg virus (MARV) and Ebola virus (EBOV), family Filoviridae, were discovered in 1967 and 1976, respectively, but remained largely unknown until 1995 when EBOV reemerged in Kikwit, Democratic Republic of the Congo (DRC). Since then Angola, DRC, Gabon, Republic of Congo, Sudan, and Uganda have experienced outbreaks of EBOV and MARV hemorrhagic fever, which varied from a few cases to several hundreds with case fatality rates ranging from 50 – 90%. In addition, EBOV has emerged as a devastating pathogen for the great apes in some of these countries leading to a dramatic reduction of these endangered species. More recently, different fruit and insectivore bats have been implicated as potential reservoirs for MARV and EBOV. Being highly pathogenic for human and nonhuman primates, and the subject of former weapon programs, makes filoviruses one of the most feared pathogens worldwide today. The lack of pre- and post-exposure intervention makes the development of rapid diagnostics, new antivirals, and protective vaccines a priority for the preparedness of many nations. Further insight into the immunology and pathogenesis of filoviruses will help to establish the urgently needed immune protective markers to evaluate experimental vaccine candidates. This chapter reviews and evaluates the current status of filovirus vaccine research, a field that has made tremendous progress in the past decade leading to several promising vaccine platforms of which one is currently in phase I clinical trials. All these platforms show excellent pre-exposure protective efficacies in macaques, the gold standard animal model, but in particular one candidate vaccine has proven promising in post-exposure treatment. It is expected that within the next decade a vaccine for MARV and EBOV will be available.