The University of Wisconsin-Madison team, led by virology Professor Yoshihiro Kawaoka, says it hopes its work will help researchers quickly develop effective new drugs to combat the fast-evolving flu and other viruses that threaten to cause widespread sickness and economic devastation.

Viruses spread by commandeering genes, proteins and carbohydrates from their victims' cells. They then shuffle and combine with other genes, producing offspring that have unique characteristics, which is one reason why flu viruses continually change.

The team, which reported its research Thursday in the scientific journal Nature, wanted to find out which genes hosted the bird flu virus. So it screened more than 13,000 fruit fly genes and narrowed the number to 100 genes and then down to three.

It then "turned off" the first three genes to see if the cell would now fight the flu. The cells resisted infection, so the scientists knew those genes were flu hosts.

It plans to do the same thing with the remaining 97 genes.

Kawaoka told the Milwaukee Journal Sentinel his team's research could speed the development of drugs for many viral diseases, including AIDS.