Ebola virus is thought to be one of the most deadly known to man, and the most recent estimates suggest that the 2013-2016 West African outbreak has killed around 40 percent of the more than 28,000 people who have had symptoms. However, a new study suggests that some people may not only be able to survive Ebola infection, but may do so without experiencing any symptoms.
Eugene Richardson from Stanford University, USA, and colleagues conducted a survey of people living in Sukudu, Kono District, Sierra Leone, a village identified as a major Ebola transmission “hotspot” between August 2014 and February 2015. The team took blood from 187 adults and children who had been in close proximity to a person with infectious Ebola but were never identified themselves as having Ebola. They then tested the blood samples for proteins known as Ebola glycoprotein antibodies, the presence of which indicates a past Ebola infection.
Fourteen of the 187 exposed individuals (7.5 percent) tested positive for Ebola antibodies. Although two of these 14 admitted having had a fever, the other 12 denied having had any symptoms. While these people may have simply not wanted to admit to having had symptoms because of stigma and fear, the researchers say their results may indicate that these individuals contracted Ebola with only mild or asymptomatic infection.
The researchers caution against extrapolating data from a single village to make generalizations about the Ebola outbreak. Nonetheless, their findings add to evidence that some people can be infected with Ebola yet experience minimal symptoms. Since asymptomatic individuals might nonetheless be infectious, the results could alter our understanding of Ebola infection and transmission.
Research Article: Richardson ET, Kelly JD, Barrie MB, Mesman AW, Karku S, Quiwa K, et al. (2016) Minimally Symptomatic Infection in an Ebola ‘Hotspot’: A Cross-Sectional Serosurvey. PLoS Negl Trop Dis 10(11): e0005087. doi:10.1371/journal.pntd.0005087
Image Credit: NIAID, Flickr