Post Reply - Pets & Pandemics

genotype B3.13

   https://afludiary.blogspot.com/2024/08/preprint-recent-bovine-hpai-h5n1.html or https://afludiary.blogspot.com/2024/08/preprint-recent-bovine-hpai-h5n1.html ;
Despite these ominous reports, human infections in the United States (n=13) have remained both rare and unexpectedly mild.  How long that happy state of affairs will last is unknowable, so it is important to better understand what is going on with those species which are currently more seriously impacted by the virus. 
To that end, we've a preprint today from researchers at the NIAID labs in Hamilton, MT that finds that the bovine (genotype B3.13) strain of HPAI H5 produces more severe neurological disease in C57BL/6J lab mice than did 3 other strains (two 2.3.4.4b isolates & a 20-year-old strain from Vietnam).
Curiously, tests on BALB/C mice produced more rapid onset of severe respiratory symptoms, but without the neurological involvement seen in C57BL/6J lab mice. While several plausible explanations were offered, the reasons remain unclear. 
-
In this study, we compared disease progression and pathology of three recent clade 2.3.4.4b isolates derived from a cow, mountain lion, and mink to a human HPAI A(H5N1) isolate from Vietnam in mice.

Inoculation of C57BL/6J and BALB/c mice with all four HPAI A(H5N1) isolates resulted in comparable levels of virus replication in the lung inducing severe respiratory disease.

C57BL/6J mice infected with the bovine isolate also developed high virus titers in the brain, resulting in a significant pro-inflammatory cytokine response and neurologic disease.

Our findings suggest the recent bovine isolate possesses enhanced respiratory and neuroinvasive/neurovirulent properties causing fatal respiratory and neurologic disease in C57BL/6J mice.
-

In conclusion, the recent bovine isolate showed high virulence for mice when inoculated by the intranasal and oral routes. C57BL/6J and BALLB/c mice provide excellent in vivo screening models for efficacy testing of antiviral, therapeutic and vaccine candidates against infections with these emerging HPAI A(H5N1) viruses.
-
Although we are currently focused on the bovine (B3.13) genotype of H5N1, there are literally dozens of genotypes of H5N1 in circulation around the world, with more being added over time. 
And as we've discussed previously, even minor genetic variations between viruses can produce vastly different characteristics (see Differences In Virulence Between Closely Related H5N1 Strains).  
While we may be comforted by the lack of severe H5N1 infection in the United States, the virus continues to rapidly evolve, making past performance no guarantee of future results. 
DJ, The main reason why we do not see more human H5N1 cases may be lack of testing & reporting..."the news is under control-NOT the disease"! 

Spread of H5N1 in mice may be a major problem around the globe...cats eat mice...

So H5N1/H5 type of flu-getting "better" in spreading in mammals does increase the risks of cats/dogs spreading H5-types of flu...

Again-CoViD may result in decrease of immunity-so other diseases get more chances !

Pets often get very close to humans...in the household privacy...Indoor cats-kept away from outdoor-shoes-is a way to further limit risks...

Outdoor cats, (playing) dogs may be a bigger risk...Maybe vets can find a market for "pet-testing" for flu/CoViD ? The most risky virusses are those that are the ones that are already in tests for humans...(But you can not put a test-swab in a tiny cat nose...). 

DJ-Again, H5N1, Mpox risks via pets are "very limited/low"...CoViD risks may be much higher...and for that matter knowing a cat/dog/pet can catch CoViD should be a warning !

Still most/almost all CoViD spread likely is human-to-human...In mammals animals eating infected animals may be a main route...

Try to avoid your pet eating dead animals or animal droppings...If a lot of wild birds were found dead in a water-do not let your dog swim/drink there...

Be aware of the risks ! Think !