I do not understand why the Michigan findings, that a dairy worker from one of the infected dairies also worked on one of the layer farms that was infected, was never followed up on. They could have tested the worker for antibodies since they obviously knew who they were, and they could have compared the viral sequences from that dairy to the one that infected the layer farm, but they did not even though it was known from the first Texas dairy worker to be infected that humans could shed live virus once infected. They made the research line of the virus cultured from the eye swabs of that Texas dairy worker. It was well understood where the virus was coming from by the time the Utah layer flock was infected with the dairy virus, and they found multiple infected dairies in the same county. Millions of layer chickens would not have had to be depopulated if they had started testing and restricting dairy workers from working on poultry farms. Look at how many commercial layer flocks California lost, and they knew the virus was coming from the dairies. Changing clothing and even showering into a clean facility will not stop a worker shedding live virus from infecting the animals at another farm.
Ron, don't follow up when you really don't want to know the answers...I'm not sure I'm in the same camp with you on the workers spreading the virus from dairies to poultry farms. I personally think viral aerosol clouds from thousands of cattle are much more likely in most cases - that is probably how the infection spread dairy to dairy in California and CO. The feedlots may have played a role also, but no one ever did PCR or ELISA's on either feedlot cattle or big dairy herds for that matter. The respiratory infection in cattle is just not remarkable enough by itself to trigger testing when people don't want to test for it...People may also spread it, but the odds and numbers favor the cattle when they outnumber people 10,000 to 1. Regardless, God forbid we get persistent in testing either species when we don't want to know the answers! Just yell HIPAA or "confidentiality" and duck...
Back to poultry houses though; when chickens are infected and people are around, this virus is mammalian adapted enough that it's stupid to discount any possibility that people could carry it via aerosol for 24-48 hours, with or without symptoms. Just systematically test to assess the possibility! For the birds' sake!!
If the Dairy infection taught us anything it should be that farm workers are a major vector for spread of the virus. The first studies in Michigan and Texas noted that dairy workers from infected farms also worked on Poultry farms. The Missouri antibody study pretty much concluded that cattle were routinely infected by human influenza A, and farm workers would have been the vector of infection. They needed to start contact tracing and testing of dairy workers early in the dairy epidemic, but it was never done. California once claimed that they were going to start dairy worker testing, but that never happened. They were already contact tracing and finding a boat load of infected dairies. Hot spots like PA are likely caused by farm workers spreading the virus to other farms.
Ron, I sure wish we could make worker testing routine for the sake of the birds! We would never let cats roam untested in poultry barns during high-risk periods, and yet we assume people are non-risky! I wonder how many wear N95's and keep them on? Shower in and out and change clothes, but don't sweat your respiration...huge biosecurity gap we don't want to address. A simple matrix flu rapid test before and after work would flag for both seasonal H1/H3 and also for H5. Reactors could be further screened. We spend way too much time fretting over whether we see symptoms to justify testing and not enough time just testing!! Virus spikes before people are aware of illness, if they ever become aware at all.
I do not understand why the Michigan findings, that a dairy worker from one of the infected dairies also worked on one of the layer farms that was infected, was never followed up on. They could have tested the worker for antibodies since they obviously knew who they were, and they could have compared the viral sequences from that dairy to the one that infected the layer farm, but they did not even though it was known from the first Texas dairy worker to be infected that humans could shed live virus once infected. They made the research line of the virus cultured from the eye swabs of that Texas dairy worker. It was well understood where the virus was coming from by the time the Utah layer flock was infected with the dairy virus, and they found multiple infected dairies in the same county. Millions of layer chickens would not have had to be depopulated if they had started testing and restricting dairy workers from working on poultry farms. Look at how many commercial layer flocks California lost, and they knew the virus was coming from the dairies. Changing clothing and even showering into a clean facility will not stop a worker shedding live virus from infecting the animals at another farm.
Ron, don't follow up when you really don't want to know the answers...I'm not sure I'm in the same camp with you on the workers spreading the virus from dairies to poultry farms. I personally think viral aerosol clouds from thousands of cattle are much more likely in most cases - that is probably how the infection spread dairy to dairy in California and CO. The feedlots may have played a role also, but no one ever did PCR or ELISA's on either feedlot cattle or big dairy herds for that matter. The respiratory infection in cattle is just not remarkable enough by itself to trigger testing when people don't want to test for it...People may also spread it, but the odds and numbers favor the cattle when they outnumber people 10,000 to 1. Regardless, God forbid we get persistent in testing either species when we don't want to know the answers! Just yell HIPAA or "confidentiality" and duck...
Back to poultry houses though; when chickens are infected and people are around, this virus is mammalian adapted enough that it's stupid to discount any possibility that people could carry it via aerosol for 24-48 hours, with or without symptoms. Just systematically test to assess the possibility! For the birds' sake!!
If the Dairy infection taught us anything it should be that farm workers are a major vector for spread of the virus. The first studies in Michigan and Texas noted that dairy workers from infected farms also worked on Poultry farms. The Missouri antibody study pretty much concluded that cattle were routinely infected by human influenza A, and farm workers would have been the vector of infection. They needed to start contact tracing and testing of dairy workers early in the dairy epidemic, but it was never done. California once claimed that they were going to start dairy worker testing, but that never happened. They were already contact tracing and finding a boat load of infected dairies. Hot spots like PA are likely caused by farm workers spreading the virus to other farms.
https://www.cidrap.umn.edu/avian-influenza-bird-flu/study-finds-influenza-antibodies-not-uncommon-us-cattle
Farm workers are likely a major vector for infecting farm animals.
Ron, I sure wish we could make worker testing routine for the sake of the birds! We would never let cats roam untested in poultry barns during high-risk periods, and yet we assume people are non-risky! I wonder how many wear N95's and keep them on? Shower in and out and change clothes, but don't sweat your respiration...huge biosecurity gap we don't want to address. A simple matrix flu rapid test before and after work would flag for both seasonal H1/H3 and also for H5. Reactors could be further screened. We spend way too much time fretting over whether we see symptoms to justify testing and not enough time just testing!! Virus spikes before people are aware of illness, if they ever become aware at all.