Rare but deadly, Ebola Virus Disease is caused by a virus thought to have originated in bats. In recent years, humans have also become reservoirs of the virus,1 spreading it through bodily fluids.2 Although there have been relatively few Ebola outbreaks since the virus was discovered in 1976, they have been devastating, with death rates ranging from 20% to 90%.
Initial symptoms are often flu-like, but can progress to liver and kidney dysfunction and internal and external bleeding.3 Treatments, such as oral or intravenous fluids and monoclonal antibodies, can greatly improve chances of survival.4 Effective vaccines against the Zaire strain of the virus have been available since 2019, but supply remains limited.5 Nonetheless, the World Health Organization (WHO) has been able to coordinate swift vaccine delivery during recent outbreaks.
In 2014-2016 and 2018-2020, gaps in detection and response led to delays that allowed two Ebola outbreaks to become epidemics. The first, in West Africa, began in Guinea and spread to Liberia and Sierra Leone, as well as seven other countries including the United States and Italy, between 2014 and 2016. Subsequent analysis pointed to failures that hampered response efforts.6