Cold Winter Linked to Pennsylvania Avian Influenza Surge
Monday, March 2nd, 2026 Catastrophe Property Risk Management UnderwritingA surge of H5N1 avian influenza has wiped out 7.4 million chickens in Pennsylvania within a single month, intensifying a national outbreak that has eliminated 196 million birds over the past four years. The most recent wave struck earlier than expected, with infections confirmed as early as January. State officials, including Josh Shapiro, have described the situation as a crisis as farms report widespread culling across egg-laying and meat-producing operations.
Industry experts suspect that unusually frigid winter temperatures contributed to the outbreak’s timing and severity. Frozen waterways may have driven wild birds, including snow geese, closer to densely packed poultry farms in Lancaster County, one of the hardest-hit areas. While poultry typically suffer fatal infections, some wild birds can carry the virus without showing symptoms, complicating prevention efforts. The disease, known as H5N1 avian influenza, has historically peaked during spring and fall migrations, but this year’s cases emerged dramatically earlier.
For property and livestock insurers, the scale and speed of the losses raise key underwriting and claims concerns. Poultry producers face not only the cost of culled birds but also business interruption, supply chain disruption, biosecurity upgrades, and potential liability exposure. Lancaster County’s dense concentration of farms increases the risk of clustered losses, testing aggregation modeling and reinsurance structures.
Adjusters handling agricultural property and livestock mortality claims should expect detailed documentation related to culling orders, state and federal indemnity programs, cleanup expenses, and downtime calculations. Weather-related factors may also come under scrutiny if insureds argue that extreme cold indirectly contributed to exposure risks. As spring migration approaches, the potential for expanded spread introduces further volatility for carriers with concentration in high-production states such as Pennsylvania, the fourth-largest egg producer nationwide.
The outbreak underscores the need for clear policy language around disease exclusions, government-mandated destruction clauses, and business interruption triggers tied to biosecurity events. With cases appearing earlier in the season, insurers may reassess risk assumptions tied to traditional migration timelines.
