Could Ancient Microbes in Polar Ice Cause Epidemics?

September 26, 1999  Syracuse, New York ­ The recent encephalitis outbreak in New York City that has killed three people and made fifteen others very ill has now been traced to a microbe called the West Nile-like virus, a bird virus never seen in the United States or the entire Western Hemisphere before, according to the Center for Disease Control. Until now, it's a virus that was only known in eastern and northern Africa and western Asia. Now CDC officials fear the dangerous virus could spread to Central and South America as birds migrate for the winter season and fly south.

How exactly this African and Asian bird virus got to the United States is not known. It might have come in an illegal import of a bird from the other side of the world. But this encephalitis outbreak and the associated human deaths show that when microbes are released into an environment where they have not been before, the microbes can be especially dangerous because what they infect has no immunity against them.