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

Scientists are sounding alarms about a genetic mutation that was recently identified in four dairy cow herds, nearly one year after H5N1 bird flu was first reported in Texas dairy cattle.

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.