16 January 2015 vol 347, issue 6219, pages 209-348
The Ebola Epidemic
High hopes for Guinean vaccine trial
The push to test Ebola vaccines in the field is accelerating. Two candidates may go into phase III trials in a matter of weeks; a third one has just entered a phase I trial. Researchers have designed very different phase III studies for Liberia, Sierra Leone, and Guinea, the three countries with ongoing virus transmission. One problem they’re facing is that the number of new cases has dropped sharply in Liberia and is beginning to ebb in Sierra Leone. That’s why many scientists say Guinea—where researchers plan to try a highly unusual ring vaccination design—is the most promising testing ground.