September 10, 2025

A backyard flock in Anne Arundel County, MD has tested presumptive positive for H5 avian influenza at the Frederick Animal Health Laboratory, part of the National Animal Health Laboratory Network. Additional samples have been sent to the U.S. Department of Agriculture’s National Veterinary Services Laboratory (NVSL) for further confirmation. This is the third case in Anne Arundel County in 2025.

The Maryland Department of Agriculture has quarantined the affected premises, and the birds on the property are being depopulated to prevent the spread of disease. Birds from the affected flock will not enter the food system.