The world is one step closer to having a vaccine to protect against Ebola. An experimental vaccine against the highly deadly virus passed its first clinical trial. The National Institute of Health in Bethesda, Maryland safely tested 20 participants who developed antibodies against Ebola. There were minor side effects, but the results were promising, researchers told the New England Journal of Medicine. The NIH is in talks with Liberia to bring the next round of vaccine testing to West Africa, and the World Health Organization wants to begin testing it on 20,000 front-line health-care workers. As of Wednesday, Ebola has claimed the lives of 5,689 people.