America should have more aggressively intervened almost a year ago.

The death in Louisiana — involving a person with underlying health conditions — is the first human case in the United States linked to exposure to backyard birds, according to the federal Centers for Disease Control and Prevention.

Medical experts advise that people should get a vaccine for the bird flu when it becomes commercially available. One doctor said the most at-risk patients should be first.

Though the bird flu has spread across multiple states in cattle and other birds, infections in mammals remain low, according to the CDC.