The aviary birds have more chance of contracting it from the birds that visit the back yard than these 2 , hand sanitisers , separate food / water bowls etc , all are used as a just in case .
Cant help it , would not be able to sleep nights if I didn't help an injured animal, to the point where Ive even stolen an abused dog from a friends neighbors yard
Old Bill the black poodle had a great life with us and lived to be a very old dog. 
However I do hear what your saying B/ Green and I have told my other half of my concern about pbf and he agrees that we may be pushing our luck and WIRES should take on any more injured birds we find .