First U.S. H5N9 Bird Flu Outbreak Detected on California Duck Farm

PARIS, Jan 27 (Reuters) – The United States has reported its first outbreak of the H5N9 bird flu strain in poultry at a duck farm in California, according to the World Organisation for Animal Health (WOAH). The outbreak, detected in Merced County, also involved the more common H5N1 strain, leading to the culling of nearly 119,000 birds by Dec. 2.

Highly pathogenic avian influenza (HPAI), commonly known as bird flu, has caused widespread devastation globally in recent years, resulting in the culling of hundreds of millions of poultry. The virus has also infected dozens of mammal species, including dairy cows in the U.S. and Louisiana. While H5N1 has been the dominant strain causing significant damage, H5N9 is far less common.

“This is the first confirmed case of HPAI H5N9 in poultry in the United States,” the U.S. Department of Agriculture (USDA) stated in a report to the WOAH. The USDA’s Animal and Plant Health Inspection Service (APHIS), alongside state animal health and wildlife officials, is conducting extensive epidemiological investigations and enhanced surveillance in response to the outbreak.

The detection of H5N9 marks a new development in the ongoing battle against avian influenza in the U.S. The virus’s ability to spread rapidly among poultry and other animals has raised concerns about its potential impact on food security and public health. Authorities are working to contain the outbreak and prevent further spread.

Bird flu outbreaks have become increasingly frequent and severe in recent years, with the H5N1 strain causing significant losses in poultry populations worldwide. The emergence of H5N9 in the U.S. underscores the need for continued vigilance and robust biosecurity measures to protect both animal and human health.