Friday, June 14, 2024

Minnesota BOAH Announces Testing Requirements for Lactating Cattle Before Exhibition

96 Herds across 12 states

#18,123


Early summer signals the start of county and state fair season across much of the Central and Northern United States, with events running well into fall.  Most of these venues feature large agricultural exhibits, where prize pigs and blue-ribbon worthy cows are put on display. 

While tens of millions of people safely attend these events every year, since 2010 we've seen a small number of novel swine variant flu infections (H1N1v, H1N2v, or H3N2v) among exhibitors, or attendees.  In 2012, over 300 (mostly mild) cases were reported. 

Roughly 500 Cases in 15 Years in the United States
 

Since most people only experience mild or moderate flu symptoms, many cases likely go unreported. During a small outbreak (n=13) of of H3N2v a dozen years ago, researchers estimated that fewer than 1 in every 200 cases was identified (see CID Journal: Estimates Of Human Infection From H3N2v (Jul 2011-Apr 2012). 

With the summer agricultural fair season about to kick off again, the CDC once again advises those who are at higher risk of serious flu complications (including children under 5, adults over 65, pregnant women, and those with certain chronic medical conditions), to avoid pigs and the swine barn altogether.

But this year, with dairy cattle across the country testing positive for avian H5N1 and a small number of spillovers into humans, there are new biosecurity considerations. While the risk to public health is probably low, there are also concerns over the movement of infected animals potentially spreading the disease to other livestock. 

In yesterday's APHIS/USDA epidemiological investigation into the spread of H5N1 in Michigan, they cited the movement of livestock, farm equipment (including trucks), and personnel as contributing to the spread of the virus.  

All of which suggests that enhanced biosecurity at agricultural exhibits - where cattle, pigs, and poultry may all be on display - is particularly important.  Exactly how much biosecurity is `enough' is one of those questions that we really can't answer right now. 

Yesterday, however, the Minnesota Board of Animal Health (BOAH) announced a major first step; requiring a negative H5N1 test for all lactating cows prior to exhibition.  

Wisconsin announced  similar biosecurity measures earlier this weekand Michigan has announced even tougher steps, although a number of states have yet to weigh in.  

The BOAH announcement, followed by some CDC guidance links. 

For immediate release: June 13, 2024
Contact: Michael Crusan
New testing requirements for dairy cows before events


The Minnesota Board of Animal Health announces new testing requirements for lactating dairy cows effective Tuesday, June 18. All lactating (currently producing milk) dairy cows must have both a negative H5N1 test result and Certificate of Veterinary Inspection (CVI) to attend any exhibition in Minnesota. The requirements are effective until December 31, 2024.

“While H5N1 influenza in dairy cases are still being studied across the country, initial insights show milk and the udders are a hotspot for influenza virus on infected cows, which makes showing lactating dairy at events a higher risk” said Senior Veterinarian of Cattle Programs, Dr. Katie Cornille. “Requiring a negative test before an exhibition reduces that risk.”

A veterinarian must oversee or collect samples from each animal traveling to the exhibition within seven days before arriving at the event. Samples must be sent to a National Animal Health Laboratory Network Laboratory like the University of Minnesota’s Veterinary Diagnostic Lab (VDL) in St. Paul. Once a negative result is received for an animal, it can move within Minnesota for 10 days from the sample collection date to locations specified on the CVI.

If samples are positive for influenza, the VDL will notify the Board of the results and the Board will contact the producer to quarantine the cows and begin a disease investigation. While this is happening the samples are forwarded to the USDA’s National Veterinary Services Laboratories for official confirmation, which is necessary for the owner to apply for any federal financial reimbursement. All results are confidential, and the Board will only report the county where a case is detected. Lactating dairy cows on the premises are under a 30-day quarantine. The Board can release the quarantine after a minimum of 30 days and a negative H5N1 milk test.

Livestock owners can find additional biosecurity recommendations for attending exhibitions on the USDA’s website. The Board has recommendations available for exhibition managers to prevent H5N1 in livestock. You can review the full copy of the testing requirement on the Board’s website.

*Editor’s note on H5N1 terminology: detections of the virus in non-poultry species should not be called, “bird flu,” instead the virus strain and species are used, “H5N1 in dairy.”
While there are a lot of unanswered questions regarding the risks from H5N1 - and the best ways to mitigate them -  CDC has published the following guidance documents for Agricultural Fair Organizers & Exhibitors

Recommendations to Minimize Influenza Transmission at Dairy Cattle Livestock Exhibitions

Highly Pathogenic Avian Influenza A(H5N1) Virus in Animals: Interim Recommendations for Prevention, Monitoring, and Public Health Investigations

Updated Interim Recommendations for Worker Protection and Use of Personal Protective Equipment (PPE) to Reduce Exposure to Novel Influenza A Viruses Associated with Disease in Humans