It all depends on the disease, the method of transmission, the incubation period, and how lethal the disease is. Usually, by the time a bird is symptomatic, the rest of the flock has been exposed. I would agree that removing the bird to separate housing would be in order for the safety of the bird.
One thing that I did not see mentioned in above posts is this: If recovery is not likely, then, it may be in the best interests of the bird to euthanize her. It all depends on your flock goals and whether you see your birds as livestock or as pets.
Also, when you have sickness in your flock, it's time to evaluate your husbandry practices: Crowding? Keeping birds on wet ground? Nutrition? Poor breeding stock? Mites or lice can show up as a result of bird's immune system being knocked down, or a bird can become ill because mites or lice are knocking her immune system down.
One thing that I did not see mentioned in above posts is this: If recovery is not likely, then, it may be in the best interests of the bird to euthanize her. It all depends on your flock goals and whether you see your birds as livestock or as pets.
Also, when you have sickness in your flock, it's time to evaluate your husbandry practices: Crowding? Keeping birds on wet ground? Nutrition? Poor breeding stock? Mites or lice can show up as a result of bird's immune system being knocked down, or a bird can become ill because mites or lice are knocking her immune system down.
