Genetically, the H1N1 virus hasn't changed much since it first appeared last April, but experience has shown influenza viruses tend to evolve -- sometimes with catastrophic results.
In 1918, a relatively mild strain of Spanish flu suddenly became much more virulent, killing millions of people in a global pandemic.
Making sure that doesn't happen with H1N1 is the goal of Dr. Charles Chu, Director of the Viral Detection and Discovery Center in San Francisco.
He and his his team are monitoring H1N1 flu samples from around the globe looking for changes in the virus that might impact the effectiveness of the vaccine or have other medical implications.
His lab is filled with freezers full of flu specimens and machinery that compares DNA from those samples with the genetic makeup of thousands of other known viruses. Within hours his team knows whether the specimen is something public health officials need to be alerted to. If they can detect new outbreaks in their earliest stages, it could save thousands of lives....