Avian influenza H5N1 infection in humans has spread to seven U.S. states, growing from 46 cases last week to 52 cases this week.

An island halfway between South Africa and Antarctica, where half of the world’s wandering albatrosses breed, is under threat ...

The H5N1 strain of avian flu is now passing easily among South America's elephant seals and drastically cutting herd populations, a new report finds. "It is likely that more than half of the ...