it could have just been new home sniffles. When stressed( and being brought into a new home/environment counts), rats can sneeze more often, and new owners or people that are unaware, think they are sick. I have pet rats, and had found one at work, and just bought new one for the found ones cagemate ( after qtining). both the found rat, and then later on, the new rat went through a few days of sneezing. It did subside, then stop after about a week. Perhaps that was just what it was. Now, not saying they werent sick or anything or couldnt have been sick, just passing on some info for you for future reference. You can always do what I call 'steam cleaning' the rats.... put them in your bathroom, in a ventilated cage, and run hot water in the shower. they the bathroom steam up, and them breathing in the warm moist air will help break anything up that may be inside them. Tho, this was info I retreived to help sick rats, I have done it in the past for new rats with new home sniffles and it seemed to help for a bit. I didnt do it this last time because I can't, we have no hot water, but it still went away as the rat adjusted to the new home.
My only suggestion to you would be to see if you can find a person locally that breeds their own rats for sale and get from them. Pet stores are the last place I get rats from, and when I do, I ask them to order them for me so I dont get ones that have been sitting around in the petstore for a while ( but to be fair, i need smaller sized rats, and best shot at getting them are ordering them). That is the only way I can think of shy from breeding your own ( which will not be possible if parent has a fear of them)
Good luck, i do personally hate having to rely on pet stores for food for my snakes.
janet kovacic