My husband, 86, is convinced he has gotten lice from out cats, (we have had them for 14 yrs), and is driving everyone wild with his home/generic treatments. I have cleaned the bedroom thoroughly, I sleep in the same bed and I am not having ny problem or symptoms. I have checked his hair, nothing on the hair itself, but he does have what I think are patches of dry scalp. Of course he scratches until he bleeds, then sprays NIT again. I have suggested a dermatologist, however he refuses to even think he could be wrong. Can you help?