Influenza A infection common in cattle

https://www.cidrap.umn.edu/avian-influenza-bird-flu/study-finds-influenza-antibodies-not-uncommon-us-cattle
https://journals.asm.org/doi/full/10.1128/jvi.02138-24?af=R
A third of 1724 (586) cattle serum samples tested positive for influenza A infection.  The samples were collected between Jan 2023 to May 2024 (most before the dairy infection started) and 1403 samples were collected in Missouri that never reported a dairy herd infected with the dairy virus (H5N1) so it wasn't surprising that they did not find any cattle infected with H5N1.  It looks like all cattle were infected with human transmissible strains or strains found in swine (also probably human transmissible).  6 samples were dual or triple positive for more than one viral strain.  They claim that they do not know how the cattle were infected, but it seems obvious that they were infected by humans as the common vector in all cases, especially with the two common human transmissible strains (H1N1 and H3N2 the current virus infecting humans this season).
This means that influenza infection of cattle is common, and humans are the likely vector for transmitting the virus to cattle.  As stupid as it may be it is still only a recommendation that dairy workers should not work at other farms if they know they work on an infected farm, and the USDA and CDC never attempted to identify all the infected farms so that the workers would have the chance to make that decision.  California never restricted dairy worker movement and it spread throughout the state, and infected over 40% of their commercial layer flocks (dairy workers also work at commercial poultry farms).
This is likely also evidence that humans brought the D1.1 H5N1 genotype into dairy cattle.  A dairy worker may have been infected by their backyard chickens or by working on an infected poultry farm and taken the virus to the dairy that they also worked at.
Ron Okimoto