A backyard poultry flock in Racine County has tested positive for highly pathogenic avian influenza, leading state agriculture officials to depopulate birds on the affected property. It marks the county's fourth recorded poultry outbreak since the current nationwide bird flu response began in 2022, and it comes as state officials renew calls for poultry owners to register their flocks and lock down biosecurity before winter sets in.
The detection was confirmed October 3, according to the Wisconsin Department of Agriculture, Trade and Consumer Protection, which maintains a dedicated registry tracking HPAI cases by county and flock size. As reported by WKOW, the birds on the property will not enter the food system, and the virus — which has circulated in wild and domestic birds across North America since December 2021 — is highly contagious and often fatal to domestic poultry.
WKOW's report, citing DATCP, notes the virus can spread through direct contact with infected birds, by commingling with wild birds or their droppings, or via equipment and clothing worn by people working with animals. The agency is urging all livestock owners, not just those near the current outbreak, to implement strong biosecurity measures, including washing hands, disinfecting equipment, restricting access to animals, and separating any new flock or herd additions for at least 30 days.
A Pattern Repeating Across Southern Wisconsin
This is Wisconsin's second avian influenza detection of fall 2026, following a commercial outbreak confirmed September 14 in Barron County that affected 79,088 birds, according to Brownfield Ag News. Hoodline previously covered that Barron County lockdown, part of a joint DATCP-USDA containment response.
Statewide, Wisconsin has recorded 26 confirmed bird flu cases in domestic poultry flocks during 2026, spanning commercial operations and backyard coops in counties including Jefferson, Walworth, and Barron, per WTMJ. The scale of this year's outbreaks has varied enormously: outbreaks on March 10, 2024, led to the depopulation of more than 3.1 million birds—commercial egg-laying pullets in Jefferson County and commercial layers in Walworth County—according to WATTPoultry.com.
Those spring depopulations carried real local employment costs. Hoodline reported that commercial egg producer Daybreak Foods temporarily laid off 87 farm caretakers and sanitation workers across two facilities, with the layoffs beginning around April 1.
Surveillance Zones and Registration Requirements
Per WKOW's report, officials may implement a 10-kilometer surveillance zone around a backyard flock diagnosed with HPAI, though the zone itself carries no movement restrictions for surrounding poultry premises. DATCP offers a mapping tool allowing owners to check whether their property falls inside an active control area or surveillance zone, and the agency has asked poultry owners to keep birds indoors when possible as migration season continues.
DATCP also reminded Wisconsin livestock owners that state law requires all livestock owners, with poultry included in that definition, to register where their animals are kept. That mandate is codified under Wisconsin Statute 95.51, enacted in 2004, which made Wisconsin the first state in the nation to require location registration for disease traceability, according to the Wisconsin Legislature. Premises registration helps animal health officials quickly communicate with flock and herd owners once an outbreak is confirmed, per WKOW. Owners who notice increased mortality or signs of illness among domestic birds, dairy cattle, or other animals can report it directly to DATCP through its animal disease reporting webpage.
Health Risk to Workers Remains the Focus
The Wisconsin Department of Health Services issued clinical protocols in July advising providers to test agricultural workers for novel influenza A if they develop acute respiratory symptoms or conjunctivitis after exposure to infected animals.
