The ongoing bird flu outbreak has led to wild bird deaths, slaughtered livestock, and hazardous conditions for dairy industry workers.

Prior exposures to specific types of seasonal influenza viruses promote cross-reactive immunity against the H5N1 avian influenza virus, according to new research from the Perelman School of Medicine at the University of Pennsylvania.

A highly pathogenic strain of bird flu is spreading south along the Antarctic Peninsula and could devastate populations of penguins and other seabirds

A new H5N1 bird flu mutation has appeared in a cluster of infected dairy cows. It's a genetic change that scientists say could not only make the virus more lethal, but increase its spread between mammals and possibly humans.

Older adults who were exposed to seasonal flu viruses that circulated prior to 1968 are more likely to have some protection against H5N1, and children would benefit more from H5N1 vaccines.