I am posting to say you really should be putting down birds that get symptoms of west Nile. Which can be equilibrium issues, tremors, and such. I didn’t and now my horse is exhibiting signs of it. Chickens can absolutely get it. Just like other species not all chickens will get sick from it but some will. Those that get symptoms become carriers and any mosquito that gets a blood meal from it could bite you or your other animals like dogs and horses that can also get it. Or your neighbors.
