What is the Deal with H5N1 in captive big cats in December?

Lack of early transparency by states and NVSL revealed by delayed postings

Is anyone aware that the United States has confirmed 6 or 7 additional fatal H5N1 infections in captive felids in December, not including 16 confirmed infections of the 20 self-reported deaths by the Wild Felid Advocacy Center in Washington state? H5N1: Big Cat Carnage- Housecat Raw Foods Threaten Meat's Flu-safe Reputation

I went to the HPAI Detections in Mammals website today to check on the Washington cases and was shocked to learn that other captive big cats have perished in the past month. See the graphic below, extracted from the web site. California had 2 big cat deaths diagnosed (locations deidentified), Colorado 3 or 4 (the mountain lion may have been non-captive?), and Idaho 1 Amur tiger. If these diagnoses were in the news, I missed them.

As I stated in the original article, given the great interest in H5N1 at this time, coupled with potential risk to human contacts with these animals in sanctuaries or zoos, why have local, state, and federal official declined to make widespread announcements regarding diagnoses of this dangerous virus in animals potentially in contact with the public?

There is another, perhaps even more troubling factor - why are so many cats suddenly dying? I don’t normally disclose “gray” or non-confirmed information. However, I believe a reliable source who states that deposited B3.13 virus sequences from the Washington state big cat isolates contain a signature mutation in one gene that closely ties them to summer of 2024 Minnesota avian B3.13 H5N1 isolates. If so, that indicates that something in the diet of those big cats may have contained virus preserved from earlier 2024 turkey outbreaks in the upper Midwest.

Like any good epidemiology puzzle, each piece of information takes investigators a step closer to solving the mystery. Live H5N1 virus in raw turkey product is no doubt a huge issue! The raw cat product recalled in the Oregon cat mortality was linked to a turkey product with manufacturer-advertised origins in “Iowa or Pennsylvania” and Iowa borders Minnesota so that purported Iowa source link is somewhat plausible.

The bigger question to me is one of open information sharing with all parties who may be feeding raw meat products to captive big cats. With multiple diagnosed cases of H5N1 mortalities, can we in good conscience fail to provide widespread public warnings that raw meat of an uncertain source has been linked to multiple big cat mortalities, necessitating extraordinary measures (cooking) to prevent further deaths pending further investigation? Diagnosticians knew or should have known by December 5-6 after a Dember 4th initial diagnosis that the WA H5N1 strain was B3.13, likely of dietary and not environmental origin. In fact, that information could have been determined even earlier at the Washington state NAHLN with partial sequencing. Early sequencing and sharing of information can save both animal and human lives - we’re at the point where not sequencing and not sharing is malpractice! Moving diagnostics downstream and democratizing information is the future of effective One Health.

I don’t know what the sequences are for the Colorado, California, and Idaho mortalities. If they are B3.13, do they match the WA strain? If so, do they have common food sources? If they are D1.1, then we are more likely looking at wild bird/ environmental contamination. Either way, transparency from the states and/or laboratories would be extremely refreshing.

Finally, I suspect that raw meat sources for sanctuaries and zoos may be the “Wild West”, especially related to microbiological standards and traceability. I can only assume that these groups will be reassessing procurement practices and testing standards in the face of new challenges that H5N1 brings to them.

FSIS is overdue to reassess the same issues, even if animal food safety is not a part of their mandate. The public will not tolerate live H5N1 virus in raw poultry or meat, and “just cook it” will never work as the critical control point. Assess the true risk and figure it out!

John