In today’s Health Alert, a new strain of bird flu - H5N9 - has been detected in the U.S. The first confirmed case was found at a commercial duck farm in California.

The bird flu has been infecting American flocks for years, leading to a series of infections and increased egg prices. But now, there's a new twist: A different strain has been detected in U.S. poultry.

First U.S. detection of virulent H5N9 strain, at a California duck farm, draws scrutiny as evidence of genetic reassortment that could trigger human outbreaks.