More than 300 dead geese and other waterfowl have been discovered in five counties, and bird flu is likely to blame, officials say.

Avian influenza spreads in birds, cows and other animals, and it can sometimes spread to people. In the United States, there has been 68 total reported human cases and one death.

Nearly 70 people in the U.S. have been reported infected with bird flu in the last year, according to data from the U.S. Centers for Disease Control and Prevention, though researchers and studies suggest that's likely an undercount.