The Hawai‘i Department of Health (DOH) State Laboratories Division detected H5 avian influenza (bird flu) at very low levels in wastewater samples collected at the Līhuʻe Wastewater Treatment Plant on Kauaʻi.

The first detection was from a sample collected on Dec. 11, 2024, that was so low that it was not considered a positive result. Samples collected on Dec. 18, 2024 and Jan. 8, 2025 had similar detections. While none is considered a positive result, the consistent very low-level detections indicate a high likelihood that H5 bird flu virus is on Kauaʻi. No H5 virus infections of birds, dairy cows, or humans have been detected on Kauaʻi to date. Detection of infected birds in the state has so far been limited to Oʻahu.

 The H5 bird flu viruses include the H5N1 subtype of bird flu virus that has spread globally in birds since its initial discovery in 1996 and recently has been detected in several mammal species including dairy cows. Wastewater testing cannot determine if the detection is specifically this H5N1 subtype of bird flu virus.

The presence of the H5N1 bird flu virus in Hawaiʻi was first confirmed in November 2024 in a backyard flock of birds in Central Oʻahu. That virus strain was a different genotype of the virus that has infected birds and dairy cows on the U.S. mainland. H5 was subsequently detected at the Hilo Wastewater Treatment Plant on Hawaiʻi Island.

 While the risk to the public remains low, bird flu can cause severe illness with a high mortality rate among certain bird populations such as poultry. Commercial poultry producers and residents with backyard flocks are strongly advised to increase biosecurity measures to reduce the likelihood of infection. Bird flu can also infect dairy cows. While pasteurized milk is safe, raw milk should be avoided.

 To report multiple or unusual illnesses in poultry, livestock, or other wild birds or animals from any island in the state, contact HDOA Animal Industry Division at 808-483-7100, or, email: hdoa.ldc@hawaii.gov Monday to Friday from 7:45 a.m. to 4:30 p.m., or 808-837-8092 during non-business hours and holidays.

Residents who believe they may have been exposed to sick birds or other wildlife should contact the Disease Outbreak Control Division Disease Reporting Line at 808-586-4586 for additional guidance.