An early immune response appears to be the key to surviving infection with Ebola virus.
In the most comprehensive scientific analysis to date, researchers from the French National Institute of Health and Medical Research (INSERM) compared the immune responses of Ebola survivors with those of patients who died from the infection during two large outbreaks in Gabon in 1996. Ebola virus kills about 70% of those infected.
The French researchers reported in the April Nature Medicine that survivors produced early increasing levels of IgG that were directed against the virus's protein coat, followed by clearance of circulating viral antigen and activation of cytotoxic T cells. However, those who died of infection had no IgG response and barely detectable levels of IgM. The researchers said patients who died from Ebola infection experienced "relentless" apoptosis of peripheral blood cells during their last 5 days of life.
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