Berlin ? It was a nightmare scenario: A scientist accidentally pricked her finger with a needle used to inject the deadly Ebola virus into lab mice.

Within hours, members of a tightly bound, yet far-flung community of virologists, biologists and others were tensely gathered in a trans-Atlantic telephone conference trying to map out a way to save her life.

Less than 24 hours later, an experimental vaccine — never before tried on humans — was on its way to Germany from a lab in Canada.

And within 48 hours of the March 12 accident, the at-risk scientist, a 45-year-old woman whose identity has not been revealed, was injected with the vaccine.

So far, so good. If the woman is still healthy by Thursday, she can consider herself safe.