The two newest cases of highly pathogenic avian influenza (HPAI) on the Delmarva Peninsula resulted in the loss of 415,0000 chickens.

On March 9, the states of Delaware and Maryland made a joint announcement that HPAI had been discovered at two locations on the peninsula. One case was a commercial pullet flock in New Castle County, Delaware, while the other was a commercial broiler flock in Queen Anne’s County, Maryland.

While the states did not disclose the size of the flocks in the announcement, the United States Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) has since disclosed that the broiler flock involved 150,000 birds, while the pullet flock included 265,000 birds.

Animal health officials from both states have quarantined all affected premises, and birds on the properties are being or have been depopulated to prevent the spread of the disease.

For both Maryland and Delaware, these are the second confirmed cases in the state. The earlier cases involved a commercial layer flock in New Castle County, involving 1,146,937 chickens, and a commercial layer flock in Cecil County, Maryland, involving 664,061 chickens.


So far in 2022, HPAI has been detected in commercial poultry in seven states. In addition to Delaware and Maryland, there have been confirmed cases in Indiana, Kentucky, Iowa, Missouri and South Dakota. There has also been a confirmed case in a commercial turkey flock in Nova Scotia, Canada.

The virus has also been confirmed in wild birds and backyard flocks in other U.S. states and Canadian provinces, but those cases, in accordance with World Organisation for Animal Health (OIE) standards, should not result in any restrictions of international poultry trade.

To learn more about HPAI cases in North American commercial poultry flocks, see an interactive map on

Read our ongoing coverage of the global avian influenza outbreak.