The U.S. Food and Drug Administration (FDA) has detected viral particles of H5N1 avian influenza in milk purchased at grocery stores, but the agency maintains that the milk supply remains safe for consumption. The FDA believes the viral particles found in milk samples are remnants of viruses killed during the pasteurization process. However, additional tests are being conducted to confirm the viability of the viruses. The FDA continues to recommend against consuming unpasteurized or raw milk due to potential health risks.