Bird flu has been making the rounds in the United States over the last year and appears to be resurging again. Here’s what you need to know.

H5N1 avian influenza continues to spread amid commercial and backyard poultry, and additional cases have been reported in domestic cats

The widening U.S. bird flu outbreak has made its way to Maryland, which has counted two cases on commercial poultry farms—one in Caroline County and another in Queen Anne's County—since the start of the year.

H5N1 vaccines have been previously licensed, and millions are in the national stockpile. But even with the news of the country’s first human death due to bird flu, vaccination isn’t yet recommended.