A new Ebola vaccine provides 100 percent protection against one of the two most common strains of the Ebola virus. The results of this trial were released in The Lancet on Thursday. Although the vaccine—known as rVSV-ZEBOV—has yet to be approved by regulators, the New York Times reports that scientists have already created an emergency supply of 300,000 doses, should another Ebola outbreak occur.
The trial was conducted on on 11,841 Guinea residents last year. None of the 5,837 people who received rVSV-ZEBOV contracted the virus; 23 of the thousands of people who participated in the study but did not receive the vaccine contracted Ebola. Scientists found that a little over half of those who received the vaccine reported “at least one adverse event in the 14 days after vaccination.” The side effects, however, were generally mild—headache, fatigue and muscle pain.
“It’s certainly good news with regard to any new outbreak — and one will occur somewhere,” Dr. Anthony S. Fauci, director of the National Institute for Allergy and Infectious Diseases, told the New York Times. “But we still need to continue working on Ebola vaccines.”
Scientists are still uncertain whether rVSV-ZEBOV will provide long-lasting immunity against Ebola.