Avian Flu Has Major Economic Costs for Dairy Industry

A new paper from a team of Cornell University researchers shows that the highly pathogenic avian influenza H5N1 virus causes severe mastitis and decreased milk production in dairy cows, a drop-off that may extend beyond the clinical outbreak period.

Economic losses due to decreased milk production, mortality and early removal from the herd were estimated at $950 per clinically affected cow for a total cost of approximately $737,500 for just the one herd the team studied. This did not include any ongoing herd dynamics or reproductive losses for this herd.

In a paper titled "The impact of influenza A H5N1 virus infection in dairy cows" published in Nature Communications, the researchers found cows clinically infected with HPAI presented a significantly increased risk of death and of premature removal from a herd of 3,876 adult cows in Ohio.

The most remarkable finding was the long duration of diminished milk production in clinically affected cows, said co-author Diego Diel, professor of virology and director of the Virology Laboratory at the Animal Health Diagnostic Center.

He says pasteurization efficiently inactivates the virus, rendering the milk safe for human consumption, but that a diminution in milk production presents an enormous financial burden to the producers of affected farms, and if added up to all affected farms, it is causing major economic losses to the United States' 9.3 million cow dairy industry.