I find this interesting! What was the quality of this pet store? Would you say the other employees took as good of care of the animals as you? Was the tank over crowded, or clean like a tank in a proper home would be?
Considering salmonella is in feces and like people said, turtles are the worst for this since they will just swim around in their own feces in dirty water, I wonder if a lot of the worst chance for salmonella comes from the early days just after returning from the petstore if there was an overcrowded cage!
Heck, another reason to make sure pet stores take better care of their animals! If they don't care if their animals get sick, they should care if they could get their customers sick.