Bay Area county sees more than 351K birds killed by bird flu

Bird flu cases are on the rise in Sonoma County after three farms tested positive for the deadly virus beginning in late October, according to recent data from the U.S. Agriculture Department.

Highly pathogenic avian influenza, or HPAI, a deadly strain of bird flu, was detected by the USDA in three Sonoma County poultry farms on Oct. 27, Oct. 28 and Nov. 5. The unnamed farms had a collective 351,700 birds killed, according to data gathered by the agency.

Last month, the Press Democrat independently found that Reichardt Duck Farm in Petaluma was the first farm to test positive in California this fall. Farm owner Phil Reichardt told the Press Democrat that his staff first noticed a few birds had died on the farm before the death count spiked. Bird samples were taken to UC Davis for analysis and later tested positive for HPAI on Oct. 24. Reichardt Duck Farm eventually euthanized 57,000 birds as a result, the Press Democrat reported. SFGATE reached out to Reichardt Duck Farm but did not hear back by publication time. 

An unnamed Sonoma farm that tested positive on Oct. 28 had a total of 231,000 birds either killed by the virus or euthanized, while the other Sonoma farm, which tested positive for HPAI earlier this month, had an estimated 63,400 affected birds.

The California Department of Food and Agriculture said on Monday that HPAI was likewise detected in El Dorado County, but no movement restrictions or quarantines have been placed on that county yet. Preliminary data from the USDA on Nov. 10 showed that one backyard farm in El Dorado County had tested for positive HPAI, affecting 10 birds. Earlier this month, movement restrictions were placed in Sonoma County on Nov. 4 “as part of rapidly containing the spread,” the state agriculture department said.

While HPAI has only been detected in four flocks across the state, the strain has already spread across the U.S. within the past month. The USDA estimates that a total of 64 flocks, or 1.65 million birds, have been affected by the strain in the past 30 days. HPAI is spread through direct contact with sickened birds; it is also known to infect dairy cattle, and in some cases, humans. Last December, Gov. Gavin Newsom declared a state of emergency when 645 dairy farms in the state tested positive for bird flu. Since 2024, 70 cases of bird flu cases have been detected in humans, with one reported death, according to the Centers for Disease Control and Prevention.

The national outbreak of HPAI was first detected in 2022 and has had devastating effects on poultry farmers, who must cull infected birds to prevent the strain from spreading. Widespread culling resulted in a 70% spike in egg prices last December and a massive egg shortage. Multiple Bay Area supermarkets placed egg carton limits on customers as a result. The egg shortage had ripple effects on local restaurant owners, who likewise struggled to keep their businesses afloat amid the unprecedented price increases.