Bird flu in the US has spread to wild animals and other species of wild and domesticated animals so it is very widespread, also there is a vaccine but poultry farms refuse to use it because of cost and it would make the meat/eggs not suitable for export, poultry producers have resorted to making their poultry farms as clean as possible, washing trucks that come onto property, making employees wash and wear protective clothing to prevent contamination and the disease still makes it onto these farms. The method we used last time we had bird flu pandemic on poultry farms was mass culling of flocks that had any infected birds, but it has not worked for long this time so the cycle of kill flock, clean everything out, raise new birds raises long term capital costs for poultry farmers in USA.