Louisiana has reported the first U.S. fatality from avian influenza. Most of the country’s human cases have been mild

A person in Louisiana who was hospitalized with a severe case of bird flu has died. The hospitalization, first announced Dec. 13, marked the first severe case of H5N1 bird flu in the United States. H5N1 is a subtype of bird flu that's been circulating among wild birds and poultry in the U.

The dead victim apparently contracted the disease directly from birds as authorities said there was no evidence of person-to-person transmission.