Monday, September 28, 2026

H5N1 in Utah Mink (Updated)

 

#19,351

A little over a month ago, in That Touch of Mink Flu (H5N1 in Utah Edition), we looked at a cryptic report of an outbreak of H5N1 at a mink farm somewhere (exact location masked) in Utah. 

The USDA Detections of Highly Pathogenic Avian Influenza in Mammals dashboard reported 7 captive American mink in Utah infected with EA H5N1 (see below).


1 To protect data confidentiality, the county and mapped locations of these detections represent the approximate location of the State capitol.
Other than this, I've found no other official local, state, or federal government statements posted online.  
Thankfully, the The Animal Welfare Institute filed a Utah GRAMA public-records request with the Utah Department of Agriculture and Food (UDAF) on August 26, requesting all records concerning HPAI in American mink from June 1 onward.
On September 17th AWI published a 61-page UDAF GRAMA records release (PDF), along with a press release. Follow the link to read it in its entirety. 
 AWI Newsroom Press Statement
 

Government records obtained by AWI highlight gaps in disease response protocol, the public health hazards of mink farming, and the urgent need to phase out the practice.
 
September 17, 2026
 
This 61-page GRAMA release consists principally of emails, text-message screenshots, internal correspondence, and one heavily redacted letter (dated Aug 26th) from UDAF to Agriculture Secretary Brooke Rollins.  

Details, such as the size and location of the farm - and number of mink affected -  are blacked out.  No response from the Ag Secretary is included. 

The UDAF qualifies their release by stating `Additional records, or portions thereof have been redacted or withheld because they contain information that is relevant to an ongoing investigation in accordance to Utah Code Ann. § 63G-2-305 (10)(a)'. 

Yesterday (Sept 27th), the Salt Lake Tribune published a sobering report:


It’s the first documented outbreak of bird flu in captive mink in the U.S., and an advocacy group is raising concerns about Utah’s response.

As we've discussed often, mink are particularly susceptible to influenza (and coronaviruses), and the way they are raised in captivity can permit the rapid spread - and evolution - of those viruses. 

As an example, in the fall of 2022 H5N1 began spreading rapidly through a large mink farm in Spain (see Eurosurveillance: HPAI A(H5N1) Virus Infection in Farmed Minks, Spain, October 2022).

This mink-derived H5N1 virus from Spain carried a rare mutation (PB2-T271A), which is believed to `enhance the polymerase activity of influenza A viruses in mammalian host cells and mice'.
 
In 2023 the CDC issued an IRAT Risk Assessment On Mink Variant of Avian H5N1, finding its scores had risen in 6 of the 10 parameters used to evaluate their zoonotic potential.

Also in 2023, Finland's fur industry was hit unusually hard by HPAI H5N1, with more than 70 fur farms infected, and > 500,000 animals culled, prompting  Finland's Institute for Health and Welfare (THL) to warn `Avian influenza poses a risk to public health – improvements to health security needed at fur farms'.

During the height of this outbreak, we looked at an excellent opinion piece (see PNAS: Mink Farming Poses Risks for Future Viral Pandemics) penned by two well known virologists from the UK (Professor Wendy Barclay & Tom Peacock) on why fur farms - and mink farms in particular - are high-risk venues for flu.

Since then we've seen several other notable outbreaks, including a reassorted swine and human-origin H3N2 in Canadian farmed mink.  Many farms, and governments, remain reluctant to provide details on outbreaks, and so we are likely only seeing the tip of the iceberg. 

Meanwhile, events such as the one in Utah, continue to occur.  Perhaps, given the reluctance to report, more often than we know.  

And contrary to the old saying, what we don't know can hurt us.