Mystery: Did Experimental Vaccine Save Ebola Accident Victim's Life?

A researcher who pricked herself with a needle containing the Ebola-Zaire virus last month is expected to come back to work at the Bernard Nocht Institute in Hamburg, Germany, after Easter. Scientists are now planning an extensive series of tests to determine her reaction to an experimental vaccine rushed in from Canada after the accident. But they may never know for sure whether the shots saved her life.