Re: The Great Epizootic of 1872

On 3/29/2025 11:41 PM, jillery wrote:

To provide a historical perspective on the effects of the current bird
flu epidemic, it's worthwhile to share what happened when undocumented
Canadian horse flu viruses illegally crossed the border into the
United States:
 <https://youtu.be/u4d_sBoCcjg>
 Not a sound was heard in the silent street,
as home from the concert we hurried.
 We found not a streetcar, carriage, nor bus,
and we felt considerably worried.
 We hailed a driver we used to know,
and hurriedly ask him the reason.
 He said as he sadly lowered his head,
"The horses were all a sneezin'."
  The first cases of horse flu were reported in Toronto Canada in
September 1872.  By the spring of 1873, it had spread to both coasts,
Cuba, and Mexico.  Although it wasn't especially fatal to the horses,
from 1% to 5%, they were incapable of labor for at least two weeks
while they recovered.
 To appreciate the epidemic's impact, almost all economic activity at
the time was powered by horses.  Imagine what it would be like today
if all electric motors and internal combustion engines suddenly
stopped working.
 

In those days it was literally horse power.  The initial dairy cattle cases in March 2024 in Texas and Michigan only had around 2% mortality, but the California herds started to have 10 to 15% mortality in September.
High density of horses and the fact that they were needed to move goods between cities and states spread the disease.  The video claims that in a city of 100,000 people there was one horse per 15 people.  Some stables were immune, but my guess is that they were just infected first, and the horses had recovered before the disease took over all the other horses.  They would have just had to have been infected 3 weeks before the peak of the epidemic in that city.
There is a difference between the economic loss due to the loss of horse power and the current egg shortage.  Horses likely spread the disease among themselves and were likely infective before showing symptoms themselves.  The density and the required distance travel spread the disease.  For poultry most of the commercial layer flocks lost in 2024 were due to dairy virus infection.  The most likely vector was dairy workers that worked on both dairies and poultry farms.  This was understood from the first commercial flock infections in Michigan and Texas where dairy workers were found to work on infected poultry farms. When Utah lost it's first commercial layer flock they immediately tested the dairies in that county and found 8 of them infected.  California did not learn and lived in denial of the dairy workers spreading the virus, and did not restrict dairy worker movements and they lost over 40% of their commercial layer flocks to the dairy virus.  They knew that dairy workers were being infected and shedding virus, and they knew that dairy workers were working at more than one dairy and also at poultry farms, but they refused to do the right thing, and it resulted in over 70% of their dairy herds being infected and the loss of over 40% of their commercial layer flocks.
Ron Okimoto