Cull them and bury them deep or incinerate them. No matter how much biosecurity you practice with them, there's too great of a risk of slipping up...and your healthy flock WILL get infected. Diseases can be carried on clothing, shoes, hands, vehicle tires and some are airborne such as Infectious Bronchitis. When you saw the sorry conditions these birds were in, you shouldve left the area and let the authorities deal with it.
^^^ That's how I feel also. Sad that people don't take responsibility for their animals.
