The Most Promising Ebola Vaccine Has Been Sitting on the Shelf for 15 Years

A long-promising Ebola vaccine has sat on the shelf for 15 years, even as Bundibugyo-related transmission raged. In 2011, three crab-eating macaques that received the vaccine showed no disease symptoms after exposure, while unvaccinated peers died in large numbers. If the vaccine had protected primates against Bundibugyo, it would likely translate to human protection, Geisbert explains. Yet the candidate has never progressed to human trials, hampered by funding gaps and limited market incentives. Researchers warn it could take months to test safety and efficacy, even as hundreds have been infected and about 200 have died in the current Congo-Uganda outbreak. The rVSV approach uses a harmless virus to deliver protective genetic instructions to the immune system.