Health officials are making a renewed call for vigilance against bird flu, but some experts are puzzling over why reports of ...

During a call with U.S. doctors this month, one CDC official noted that there is a seasonality to bird flu: Cases peak in the ...

The most recent infections confirmed by the Centers for Disease Control and Prevention were in early February.

How dangerous is it? Where did it come from? H5N1 influenza’s origins stretch back to the 1990s, and key events paved the way ...