Vapona = Dichlorvos = DVDP which is still the active ingredient in Hot Shot pest strips.
http://www.drugstore.com/qxp88409_33...pest_strip.htm
These strips have been "recommended" for years. There are no accepted safe guidelines for using them around reptiles - as a matter of fact, there are more horror stories about their effects on young snakes and specific species than you will find with PAM, Black Knight, RID, Ivermectin, etc. combined.
I personally used these strips several times before PAM and other permethrin based alternatives were on the market and had numerous issues. Exposures that had no effect on some species resulted in neurological symptoms in others. Small exposure levels almost ALWAYS resulted in noticeable agigtation in my neonates. The manufacturer of these strips even recommends that they not be used in even well-ventilated rooms occupied by human beings for more than 4 hours a day.
Since PAM has been on the market, I have used it repeatedly- I have used it around small snakes, I have used it around many, many different species. It has ALWAYS been effective and it has NEVER caused any issues with my animals.