The Wisconsin Department of Agriculture Trade and Consumer Protection is requiring lactating dairy cows to be tested for influenza A before movement to fairs and exhibits.  This action has been taken following diagnoses of bovine influenza-H5N1 on close to 100 dairy herds in twelve states to date.

Given the importance of movement of live cattle in the dissemination of H5N1 among dairy herds, it is questioned why state fairs and exhibitions should accept dairy animals irrespective of age.  It is general practice to cease exhibiting poultry under conditions of high risk for avian influenza.  Cattle consigned to fairs and exhibits may be influenza-negative at the time of arrival but may be infected by an undetected avian or bovine case and then carry virus back to the home farm.  The low risk of possible human infection should be weighed against the profound consequences of an occurrence suggesting prudence in exhibitions in 2024.

In addition to H5N1 infection in commercial herds and flocks, the virus is now widespread among domestic free-living birds, small mammals including ubiquitous mice and is no longer limited to migratory waterfowl thereby increasing the risk of infection.