ABSTRACT

One notable feature of the Ebola epidemic in West Africa that began in 2014 was uncertainty about how the disease spread, despite nearly four decades of scientific and epidemiological research. In the three countries affected and then in the rest of the world, the message went out from health officials that it was only possible to contract Ebola when the body fluids of an infected person directly entered another person, either through broken skin (a wound or rash) or mixing with the fluids of the mouth, eyes, or nose. This characterisation made Ebola a disease spread by contagion in the restricted sense that it was only possible to catch by direct contact with the body fluids of an infected person. Diseases transmitted in this way are very few in number; more generally contagion refers to diseases spread by close proximity to an infected person.