Hisser has perhaps five scabs along his spine and near the base of his tail. He is not particularly trying to itch there. I don't think it's fleas. My two are inside cats, neither has gotten out in months, and they get flea treatment. When Hisser did get some fleas a while ago (still don't know how) he had allergic reactions. Acted sick, threw up his food, lethargic, pinched face. There are lots of cats in the general neighborhood. Some come on the front porch at times. What is this likely to be now?