Will Falconer, DVM Moderator
This is a really valuable discussion to have with your vet, Lorraine, and it points out the fear I have of overly interpreting titer tests. You'll want to read this page to understand a fallen titer does NOT mean a lack of immunity! Those who "swear by" titers all need to know the downside of them: when they run low, Dr. WhiteCoat will want to vaccinate again.
That's where you've got to be a step ahead in your understanding.
Your dog is highly likely immune for the rest of her life to distemper and the others. "Any titer" means there was a response, correct. An immune response was made, and immune memory cells are established now, titer or no. Please don't allow another vaccine. It would not be useful and could well be damaging.