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Avian influenza

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Avian influenza, also known as bird or avian flu, is a highly contagious virus that can affect different kinds of birds. It usually starts in wild waterfowl but can spread to chickens, turkeys, pheasants, quail, ducks, geese and guinea fowl, as well as other birds that live with people. The disease can pass from bird to bird or through contact with contaminated people, food or equipment.

As with human influenza, avian flu is a seasonal virus. Some types of avian influenza are more serious than others. High pathogenic avian influenza, the one found in Sonoma County, is very serious and can lead to many birds getting sick and dying.

This year, HPAI has been found in many places in California, including Sonoma County. According to the U.S. Animal and Plant Health Inspection Service, as of Dec. 20, 33 commercial flocks and 22 backyard flocks, representing more than 4.5 million birds, have been affected in California in this outbreak.

Avian Flu outbreak in Sonoma County

The discovery of HPAI at 10 different sites in southern Sonoma County has required more than 1 million birds to be euthanized.

As a result of the outbreak, the Sonoma County Board of Supervisors declared a local emergency on December 5, 2023. The detection of the virus was announced following an investigation by the California Department of Food and Agriculture and California Animal Health and Food Safety Laboratory System, in coordination with the U.S. Department of Agriculture’s National Veterinary Services Laboratories. The Sonoma County Department of Agriculture is participating in the local response.

To protect other flocks in the region and elsewhere in California, the locations of the detected infected flocks are currently under quarantine, and more than 1 million birds have been destroyed. The emergency proclamation by the Board of Supervisors provides additional public safety and emergency services to mitigate the effects of the disaster, including local emergency assistance for businesses that are impacted by the disease outbreak.

For more details, read the full press release.

For the latest news from California Food and Agriculture, visit Avian Influenza Updates.

Low risk to human health

According to the Centers for Disease Control and Prevention, the risk of getting sick from avian influenza is LOW. To take protective actions around birds, CDC recommends that you AVOID:

  • Direct contact with wild birds
  • Unprotected contact with domestic birds
  • Touching surfaces that may have the saliva, mucus or feces of wild or domestic birds.

In addition, CDC recommends that if you have direct contact with infected birds and become sick, you should isolate yourself, seek medical attention and notify your local or state public health department.

For employers: reduce risk by reducing exposure

Here are some resources for employers that specify how to reduce risk by reducing exposure to their workers:

Report sick or dead birds

If you encounter a sick or dead wild or domestic bird, California Department of Food and Agriculture urges you to:

  • DOMESTIC: Report any unusual or suspicious sick or dead domestic, pet or collection birds IMMEDIATELY via the CDFA’s Sick Bird Hotline at (866) 922-2473.
  • WILD: Report any unusual or suspicious wild bird deaths to the California Department of Fish and Wildlife here.

How to prevent an outbreak in your backyard flock or commercial operation

Backyard Flock:

  • Keep your distance: Restrict access to your property and birds.
  • Keep it clean: Clean and disinfect clothes, shoes, equipment and hands.
  • Don’t haul disease home: If you have been near other birds or bird owners, clean and disinfect poultry cages and equipment before going home.
  • Don’t risk disease from your neighbor: Do not borrow lawn and garden equipment, tools or poultry supplies from other bird owners.
  • Know the warning signs: Sudden increase in bird deaths, sneezing, coughing, nasal discharge, watery or green diarrhea, lack of energy, poor appetite, drop in egg production, swelling around the eyes, neck, and head, and purple discoloration of wattles, combs, and legs.
  • Do not visit other poultry farms or allow people who have been in contact with poultry farms or wild or domestic birds to visit your farm or contact your birds.

Commercial Flock:

  • Keep an “all–in, all–out” philosophy of flock management: Avoid skimming flocks. Birds left behind are exposed to work crews and equipment that could carry poultry disease viruses. Process each lot of birds separately. Clean and disinfect poultry houses between flocks.
  • Protect poultry flocks from coming into contact with wild or migratory birds: Keep poultry away from any source of water that could have been contaminated by wild birds.
  • Permit only essential workers and vehicles to enter the farm.
  • Provide clean clothing and disinfection facilities for employees.
  • Thoroughly clean and disinfect equipment and vehicles, including tires and undercarriage of vehicles arriving at or leaving from your location.
  • Do not loan to, or borrow equipment or vehicles from, other farms.
  • Change footwear and clothing before working with your own flock after visiting another farm or live-bird market or avoid visiting another bird farm if possible.
  • Avoid visits or work between multiple poultry sites under your control.
  • Do not bring birds from slaughter channels, especially those from live–bird markets, back to the farm.

For more information, see USDA’s Questions and Answers: Protecting Birds from Avian Influenza.