Avian influenza found in South Carolina

[Sally PB]

https://www.microbiologyresearch.org/content/journal/jgv/10.1099/jgv.0.001852

Link from another thread.

 

[RoyalChick]

https://www.microbiologyresearch.org/content/journal/jgv/10.1099/jgv.0.001852

Link from another thread.

I need to go back and read this properly as I am tired and just skimmed.
But it looked like this turns everything on its head. Not very contagious in chickens?
I read the findings as saying (relative to ducks) that chickens were less likely to get infected but if infected would die.
So why are we culling all the chickens?
Apologies if i misunderstood through not reading carefully enough.

 

[U_Stormcrow]

I need to go back and read this properly as I am tired and just skimmed.
But it looked like this turns everything on its head. Not very contagious in chickens?
I read the findings as saying (relative to ducks) that chickens were less likely to get infected but if infected would die.
So why are we culling all the chickens?
Apologies if i misunderstood through not reading carefully enough.

Nope, you mostly got it right. This particular strain of AI, though it is one of the H5N1 varieties, isn't particularly deadly or transmissible in chickens, though its highly transmissible in ducks.

Nothing particularly noteworthy. Like comparing strains of the flu - some are worse than others.

The decision was made, by our Gov't and others, to destroy all birds potentially infected with certain strains- H5 (any N) or H7 (any N), but not to cull for the other H varieties, because those two clades have proven to morph into highly pathologic versions in the past with regularity. China, I think, is no considering potentially culling for H11? (they tried some vaccines against some of the H5 and H7 varieties, with some effectiveness, then started seeing increase in HPAI from other clades...) Its like whackamole. But its an Influenza A virus - they've proven highly adaptable - eradication is a pipe dream.

 

[Awaytome]

"Although H5N1-21 was less infectious in chickens compared to ducks, infection in chickens always resulted in death (Fig. 2a), with an MDT of 3.1 days in the high-dose chicken group which was shorter than in the corresponding high dose duck group (Table S1). A single infected chicken in the medium-dose group also succumbed to infection rapidly at 2 dpi. Three of the five chicken deaths were characterized by a rapid clinical deterioration, as no obvious clinical signs had been observed at earlier timepoints (Table S1). However, the other two chicken mortalities were welfare-based euthanasia interventions guided by increasing clinical signs which most frequently included loss of balance, lethargy, and closed eyes (Table S2)."

 

[U_Stormcrow]

"Although H5N1-21 was less infectious in chickens compared to ducks, infection in chickens always resulted in death (Fig. 2a), with an MDT of 3.1 days in the high-dose chicken group which was shorter than in the corresponding high dose duck group (Table S1). A single infected chicken in the medium-dose group also succumbed to infection rapidly at 2 dpi. Three of the five chicken deaths were characterized by a rapid clinical deterioration, as no obvious clinical signs had been observed at earlier timepoints (Table S1). However, the other two chicken mortalities were welfare-based euthanasia interventions guided by increasing clinical signs which most frequently included loss of balance, lethargy, and closed eyes (Table S2)."

HPAI is defined by mortality. Otherwise its LPAI.

90% plus mortality? HPAI. Sub 90% LPAI.

 

[RoyalChick]

Nope, you mostly got it right. This particular strain of AI, though it is one of the H5N1 varieties, isn't particularly deadly or transmissible in chickens, though its highly transmissible in ducks.

Nothing particularly noteworthy. Like comparing strains of the flu - some are worse than others.

The decision was made, by our Gov't and others, to destroy all birds potentially infected with certain strains- H5 (any N) or H7 (any N), but not to cull for the other H varieties, because those two clades have proven to morph into highly pathologic versions in the past with regularity. China, I think, is no considering potentially culling for H11? (they tried some vaccines against some of the H5 and H7 varieties, with some effectiveness, then started seeing increase in HPAI from other clades...) Its like whackamole. But its an Influenza A virus - they've proven highly adaptable - eradication is a pipe dream.

Got it. Thanks. I need to pay more attention to strains when I am reading this sort of thing.

 

[Sally PB]

90% plus mortality? HPAI. Sub 90% LPAI.

Somehow, 89% mortality wouldn't sound low to me. Or even 50%. I'm wondering why the cutoff is 90%...?

 

[U_Stormcrow]

Somehow, 89% mortality wouldn't sound low to me. Or even 50%. I'm wondering why the cutoff is 90%...?

Its an exercise in arbitrary line drawing.

 

[idealpoultry]

Yes, TSC is a large company. I'm surprised they don't source from Ideal in TX as well...

We did ship for TSC about 10-12 years ago, but we have chosen not to work with them. They wanted all of our product during the peak time of the year, and we have stores that have been with us since the 70's and early 80's, and we did not want to leave them without a supplier. Occasionally, we will drop ship to some stores for other hatcheries.

 

[Sally PB]

we have stores that have been with us since the 70's and early 80's, and we did not want to leave them without a supplier.

Thank you.

Having worked for a small business, good suppliers are a huge help.