I tend to agree with longterm. For me though, it hasn't spread to my long-term kissing partners, which leads me to believe the root of my problem is not a pathogen (or if it is, my immune system is terrible compared to others).
Anyway, in answer to your question goldstandard, just go gentle and all tongue with it.
I passed up a "make-out-with-a-stranger" room at a Halloween party last night. Would have been fun, but I don't want anyone messing up my progress.