An Ebola virus vaccine tested during the recent 2013-2016 outbreak in West Africa appears to be highly effective. The vaccine, called rVSV-ZEBOV, was evaluated in more than 4,000 patients who were contacts or contacts of contacts during the recent epidemic. Researchers administered the vaccine either immediately or delayed 21 days in a randomized fashion. No cases of Ebola occurred 10 or more days after randomization in the immediate vaccination group vs. 16 cases in the delayed vaccination group. An additional 1,700 contacts, including 200 children, also subsequently received immediate vaccination, with no cases of Ebola noted in vaccinated individuals. The authors suggested that rVSV-ZEBOV offers substantial protection against Ebola virus disease, with no cases among vaccinated individuals from day 10 after vaccination (Published online Dec. 22, 2016, doi: http://dx.doi.org/10.1016/S0140-6736(16)32621-6).