UC Davis veterinarians are warning backyard chicken owners to take steps to protect their birds as particularly strong strains of avian influenza make their way into Northern California.
While not a public health concern for people, the two strains detected in waterfowl in Butte and Yolo counties are consistent with the H5N2 and H5N8 strains and are considered highly dangerous for chickens. Owners should enclose chickens in netting to keep them away from wild animals and store feed bags in a secure place, the vets said.
Sacramentans have joined others around the country in embracing urban chicken-keeping. A 2011 city ordinance allows city residents to keep up to three hens in backyard coops. There were 233 licenses issued in Sacramento in 2014, according to Gina Knepp of the Front Street Animal Shelter. She added that this number is likely significantly lower than the actual number of hens residing in the city limits because chicken owners often don’t obtain the required licenses.
So far, there have been no domestic cases of these strains of avian influenza, but Maurice Pitesky of the UC Davis School of Veterinary Medicine said he wouldn’t be surprised to see cases in backyard birds.
“The problem is there are all different levels of biosecurity for backyard birds,” Pitesky said. “People can carry the virus on their shoes and car tires and easily transmit it to their birds.”
The California Department of Food and Agriculture recommends that owners put aside a set of clothing and shoes for interacting with their chickens.
There are not many symptoms of bird flu. The main indicator is the high mortality rate, which may approach 100 percent for these strains, according to Pitesky. However, rare symptoms include a drop in egg production, swelling or bruising of the head and neck, diarrhea or difficulty walking.
Greg Howes, co-owner of artisan chicken coop company Two Flew the Coop, recommends that chicken owners do a visual inspection of their chickens when they let the birds out in the morning and when they lock them back up at night to make sure they’re behaving normally. He also recommended vigilance about sanitation, including washing hands before and after handling chickens and restricting visitors to the backyard poultry.
“When people have chickens, neighbors and friends want to come over and see them, but the best-case scenario is to limit the exposure of your flock,” said Howes. “These are measures we should think about at all times, not just in flu season.”
Wild waterfowl and wild animals such as rodents can carry the virus without showing any symptoms. Chicken owners with backyard ponds or who live near water should be especially careful to keep their chickens enclosed, as wild waterfowl like to congregate in these places.
Stephanie Duncan, 35, of Land Park, said she doesn’t see any waterfowl in her backyard. She and her roommate decided to let their three chickens roam around their yard on a daily basis, but not before doing research on the small doves and finches that are the only birds to come to her backyard. She found these birds are less susceptible to avian influenza than waterfowl. Duncan keeps her birds in an enclosed coop at night and their feed tightly locked in galvanized containers.
“I’m taking some extra precautions,” Duncan said. “I’ve stopped filling the wild bird feeders in my yard, even though the wild birds in my area don’t usually carry influenza. I just want to make sure my birds are safe.”
There are more wild birds than usual in the Sacramento area right now because the city is located along the Pacific Flyway, a major north-south migratory path for waterfowl.
“During the winter there are approximately eight times the number of waterfowl in California than what we will see three months from now,” Pitesky said.
Highly pathogenic avian influenzas, meaning they have a high mortality rate, are rare in North America. There hasn’t been a major outbreak of “high-path” bird flu among domestic birds since 1986. So far, the cases found in California, Washington, Oregan and British Columbia do not constitute an outbreak, but these strains are particularly strong. “Low-path” influenzas are identified regularly, but are easily taken care of.
In California, there have been no cases reported in domestic flocks, but Knepp said backyard chicken owners could be misidentifying the cause of death for their birds. Commercial flocks are tested regularly and have shown no signs of avian influenza.
“Commercial owners do a very good job of biosecurity,” Pitesky said.
Pitesky said any domestic chicken owner whose birds get sick or die should submit the bird or carcass to the California Animal Health and Food Safety Laboratory for treatment or autopsy so the department can keep a close eye on the progression of the disease.
Owners of sick or recently deceased birds should call their veterinarian and the sick bird hotline at (866) 922-2473.
Call The Bee’s Ellen Garrison at (916) 321-1006.