An outbreak of highly pathogenic avian influenza affected only one poultry house at a Foster Farms turkey operation in Stanislaus County, California, the World Organisation for Animal Health (OIE) reported. The presence of H5N8 avian influenza was confirmed at the Foster Farms turkey ranch on January 24, making it the first commercial poultry operation to be infected by the virus since it first entered the Pacific Flyway in late 2014.

According to OIE's report on the case, 145,000 birds were susceptible, with 4,500 deaths. An additional 1,200 turkeys were destroyed. Only one house of 9,000 birds was affected.

The property, which is in a remote location, has been quarantined, and movement control inside the United States has been implemented. The affected premises has been disinfected.


OIE believes the infection at the turkey farm is related to the recent avian influenza events in wild birds in the region. The virus was discovered at the Foster Farms facility as a result of increased biosecurity measures at all of Foster Farms’ East Coast facilities as avian influenza has spread through the Pacific Flyway.

Samples from the infected flock, which experienced increased mortality, were tested at the California Animal Health & Food Safety Laboratory System (CAHFS) and the USDA’s Animal and Plant Health Inspection Service (APHIS) National Veterinary Services Laboratories in Ames, Iowa, confirmed the finding. Foster Farms has been working closely with APHIS and the California Department of Food and Agriculture (CDFA) throughout the ordeal.

The cooperation of involved parties has drawn the praise of the National Turkey Federation (NTF). “USDA’s effective response to target avian influenza at a remote central California turkey ranch underscores why consumers can be secure in the fundamental safety of the food supply and continue to enjoy turkey,” said Lisa Wallenda Picard, NTF vice president of scientific and regulatory affairs.