Mites can be contracted in many ways. Where did you get it? Exposure to a mite infected bird is all it takes. If a bird he used to be with was exposed to outdoor sparrows or such, he could get it from them, and transfer it to your birds. Keep your birds away from this one and give them all the meds your vet gave you. Best to prevent the spread within your home. Also, be aware that some mites can pass on to you as well. Wash your hands and be clean about this issue.