Ebola vaccine trials raise ethical issues

The Ebola virus keeps spreading in West Africa and some researchers say that a vaccine is necessary to halt the epidemic. The two most advanced candidates have recently entered safety trials, and if they do not cause harm and trigger the immune response scientists hope to see, the World Health Organization (WHO) has recommended jumping straight into what amount to phase III efficacy tests in Liberia, Guinea, and Sierra Leone. But difficult questions are now emerging about how to design clinical trials, who should be the first to get the shots, and when to begin mass production. For instance, at a consultation held by WHO, there was broad support for randomized controlled trials. But some, like Doctors Without Borders, say such a trial, in which some subjects are assigned to a control group that doesn’t receive the actual vaccine, is unethical.