The U.S. Department of Agriculture’s National Veterinary Services Laboratories has confirmed that three adult harbor seals in Puget Sound have tested positive for the Highly Pathogenic Avian Influenza H5N1 strain. The seals stranded on Marrowstone Island on August 18 and 25. This confirms initial testing by the Washington Animal Disease Diagnostic Laboratory, which indicated the presence of H5N1 in these seals. No seal pups have tested positive.