The United States reported the first outbreak of the deadly H7N9 bird flu on a poultry farm since 2017, as the country continues to grapple with another bird flu strain that has infected humans and caused egg prices to hit record highs.

The first outbreak in the U.S. of deadly H7N9 bird flu strain since 2017 was detected in a Mississippi poultry farm, raising fresh health concerns.

The Mississippi Board of Animal Health (MBAH) late last week reported a highly pathogenic avian flu outbreak in commercial poultry, which involves the H7N9 strain—a virus type that hadn't been identified in poultry in the United States since 2017.