Vaccinated Chickens Transmit Marek's Virus and Can Kill Your Unvaccinated Chickens.

Outta Here

Songster
May 17, 2021
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Never, ever mix vaccinated and unvaccinated chickens. Marek's vaccination is what they call a "leaky" vaccination in that it prevents death of the host but does not prevent infection or transmission, and it allows the virus to become increasingly "hot" or more deadly. Vaccinated chickens who become infected (asymptomatically or not) transmit 10,000 times more of the deadly virus than an unvaccinated bird. Because of the way a leaky vaccine causes the virus to evolve, the virus is now so strong now that it has the capability of killing 100% of unvaccinated chickens the vaccinated chicken comes into contact with. Always ask whether the chickens have been vaccinated before adding them to your flock. Chicks bought from Tractor Supply stores are not vaccinated. Chicks bought from Ace Hardware are.

Research Marek's Vaccine. This is a known fact (and snowballing problem) in the commercial poultry world, threatening the very existence of chickens in the future. The first vaccine of 1970 eventually stopped working, so a second was developed in 1983, and when that began to fail, a third, which is what we are on now. The virus keeps evolving hotter strains (killing far more unvaccinated chickens than it did before the vaccine was developed). These variants are increasingly resistant to vaccination (killing more and more vaccinated chickens). Here's just one part of one article about a disease ecologist's experiment and findings:

"Read’s group started their investigation by exposing vaccinated and unvaccinated Rhode Island Red chickens to one of five Marek’s disease strains that ranged from hot to cold. The hottest strains killed every unvaccinated bird within 10 days, and the team noticed that barely any virus was shed from the feathers of the chickens during that time. (The virus spreads via contaminated dust in chicken coops). In contrast, vaccination extended the lifespan of birds exposed to the hottest strains, with 80 percent living longer than two months. But the vaccinated chickens were transmitting the virus, shedding 10,000 times more virus than an unvaccinated bird.....“One way to look at that experiment is that shows vaccinating birds kills unvaccinated birds. The vaccination of one group of birds leads to the transmission of a virus so hot that it kills the other birds, said Read said. “If you vaccinate the mothers, the same thing happens. The offspring are protected by the maternal antibodies of the mother and that allows the virus in the chicks to transmit before they kill the host. So they transmit and kill the other individuals.”

https://www.pbs.org/newshour/science/tthis-chicken-vaccine-makes-virus-dangerous
https://www.healthline.com/health-n...n-produce-stronger-versions-of-viruses-072715
https://www.quantamagazine.org/how-vaccines-can-drive-pathogens-to-evolve-20180510/
 
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Vaccinated chickens can only transmit the disease if they get it first. The vaccine does not give them Marek’s. Just something to keep in mind.
No, the vaccine does not given them Marek's, and yes they have to get the virus to transmit it as asymptomatic spreaders. The disease is widely present among every continent that has chickens--and the vaccine doesn't prevent contacting the disease. When vaccinated chickens do get it, they massively shed the virus which has evolved so unnaturally "hot" via vaccination that the normal immunity of an unvaccinated chicken can't withstand it.
 
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That’s true, I just wanted to clarify for anyone reading your post.
No, the vaccine does not given them Marek's, and yes they have to get the virus to transmit it as asymptomatic spreaders. The disease is widely present among every continent that has chickens--and the vaccine doesn't prevent contacting the disease. When vaccinated chickens do get it, they massively shed the virus which has evolved so unnaturally "hot" via vaccination that the normal immunity of an unvaccinated chicken can't withstand it.
 
Oh, thanks for pointing that out. I went back and edited where it might not have been clear. I think this is better: The words I added are in bold: "does not prevent infection or transmission, and it allows the virus to become increasingly "hot" or more deadly. Vaccinated chickens who become infected (asymptomatically or not) transmit 10,000 times more of the deadly virus than an unvaccinated bird.
Thanks for the heads up!
 
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Never, ever mix vaccinated and unvaccinated chickens. Marek's vaccination is what they call a "leaky" vaccination in that it prevents death of the host but does not prevent infection or transmission, and it allows the virus to become increasingly "hot" or more deadly. Vaccinated chickens who become infected (asymptomatically or not) transmit 10,000 times more of the deadly virus than an unvaccinated bird. Because of the way a leaky vaccine causes the virus to evolve, the virus is now so strong now that it has the capability of killing 100% of unvaccinated chickens the vaccinated chicken comes into contact with. Always ask whether the chickens have been vaccinated before adding them to your flock. Chicks bought from Tractor Supply stores are not vaccinated. Chicks bought from Ace Hardware are.

Research Marek's Vaccine. This is a known fact (and snowballing problem) in the commercial poultry world, threatening the very existence of chickens in the future. The first vaccine of 1970 eventually stopped working, so a second was developed in 1983, and when that began to fail, a third, which is what we are on now. The virus keeps evolving hotter strains (killing far more unvaccinated chickens than it did before the vaccine was developed). These variants are increasingly resistant to vaccination (killing more and more vaccinated chickens). Here's just one part of one article about a disease ecologist's experiment and findings:

"Read’s group started their investigation by exposing vaccinated and unvaccinated Rhode Island Red chickens to one of five Marek’s disease strains that ranged from hot to cold. The hottest strains killed every unvaccinated bird within 10 days, and the team noticed that barely any virus was shed from the feathers of the chickens during that time. (The virus spreads via contaminated dust in chicken coops). In contrast, vaccination extended the lifespan of birds exposed to the hottest strains, with 80 percent living longer than two months. But the vaccinated chickens were transmitting the virus, shedding 10,000 times more virus than an unvaccinated bird.....“One way to look at that experiment is that shows vaccinating birds kills unvaccinated birds. The vaccination of one group of birds leads to the transmission of a virus so hot that it kills the other birds, said Read said. “If you vaccinate the mothers, the same thing happens. The offspring are protected by the maternal antibodies of the mother and that allows the virus in the chicks to transmit before they kill the host. So they transmit and kill the other individuals.”

https://www.pbs.org/newshour/science/tthis-chicken-vaccine-makes-virus-dangerous
https://www.healthline.com/health-n...n-produce-stronger-versions-of-viruses-072715
https://www.quantamagazine.org/how-vaccines-can-drive-pathogens-to-evolve-20180510/
I believe this happened to my flock. I bought vaccinated chicks online. At 3 weeks old I added them to the barn-coop separated by wired wall. 2 weeks later a 14 wk pullet (unvaxed) dies. Same week another pullet becomes paralyzed and dies after a few days. My question is now, do I rehome the vaxed babies to save my other chickens or is it too late? Will the rest get it and die too?
 
I believe this happened to my flock. I bought vaccinated chicks online. At 3 weeks old I added them to the barn-coop separated by wired wall. 2 weeks later a 14 wk pullet (unvaxed) dies. Same week another pullet becomes paralyzed and dies after a few days. My question is now, do I rehome the vaxed babies to save my other chickens or is it too late? Will the rest get it and die too?
Definitely do NOT rehome chickens who may have Marek’s. If they did introduce Marek’s into your flock all your birds are already carriers. How old were the chicks when you bought them? Were they from a hatchery or a private breeder?
 
Definitely do NOT rehome chickens who may have Marek’s. If they did introduce Marek’s into your flock all your birds are already carriers. How old were the chicks when you bought them? Were they from a hatchery or a private breeder?
I got the vaccinated chicks as day old chicks from Meyer hatchery online. I won’t rehome anyone.
 

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