Since the summer, the U.S. has begun preparing about 10 million doses of a vaccine that they think will be effective against H5N1 bird flu. Federal officials have elected not to u

A non–peer-reviewed study published on the preprint server bioRxiv suggests that highly pathogenic avian influenza (HPAI) virus shed in poultry droppings can be transmitted by the wind, a possibility that other experts say can't be ruled out but is also very difficult to prove.