*sigh*

It's not a boa only disease. You can just as easily bring it into your collection via a BP, or any other boid... any python or boa can carry it.

Fortunately, the disease is incredibly rare. Just take precautions when bringing any new snake into your collection. Keep it away from your other snakes, wash your hands between handlings, get them vet checked if anything seems out of the ordinary, etc.