Corn Snakes -Persistent, Severe Respiratory Infection? Sinus Problems?

Hi all,

My vet and I have been battling this together for a while and I figured I would post here and see if anyone else had any clue what might be going on.

First scenario is my 6 year old corn snake female, Sharra. Sharra was perfectly healthy, laid eggs two years in a row with no problems. I moved to a new home and a few months afterward I noticed that Sharra started sneezing. The first thing I did was pull her water dish and move her to a permanent heat mat for a few days. That seemed to make the "sneezes" go away for about a week before they came back...This goes back and forth a few times before I take her to the vet and get a Rx for Baytril. We go through the whole regime of Baytril, she seems better - She has a voracious appetite, there's no wheezing or open mouthed breathing, just some sniffles. She seems better. A few weeks after the Baytril, I hear sneezes again? I take her back to the vet and he does a bacterial culture on her sputum/mouth area. It comes back completely clean, and all other tests are normal. He is not solely a reptile vet, but he is baffled but he thinks maybe she has some kind of sinus problem or is allergic to aspen, and to keep her strictly on newspaper. I have been doing so. The snake is still sneezing, but is otherwise fine. Can snakes have sinus problems!?

About 2 weeks before we took Sharra in for a culture, I had two other corn snakes get sick simultaneously, Argent and Adore. They were no where near Sharra, and as it turns out Sharra apparently is "healthy with sinus problems", there were no other sick snakes in the room, so both of them get very sick simultaneously and it's very weird. Both Argent and Adore are wheezing, sneezing, open gaping mouths, the whole 9 yards. However they are still eating voraciously. I put them on full time heat pads, switch to paper towel bedding, clean it every other day, and start a regime of Baytril. I figured this time I knew for certain it was a Respiratory infection due to all the classic symptoms, so we did not do a bacterial culture.

It's my understanding that generally when someone is sick, the doctor gives you antibiotics. They prescribe you a full regiment of antibiotics, but you normally feel better after the first two treatments, right? Well..Both Argent and Adore have today had their full treatment plan of Baytril (one injection every 5 days), and they are both still wheezing, sneezing, and gaping mouths at me. They're both still eating.

I am going to take one or both in for a culture Wednesday, but I have no idea what could really be the problem here? They are on paper towels. They are at about 85-90 degrees. They have a small water bowl. They're eating. They've gotten their injections. I put electrolytes in their water as well. I cannot even figure out how they got sick to begin with. I have always kind of felt like Baytril would do the job. My vet is NOT a reptile specialist and he kind of goes with what I suggest that I've been told from reptile vets that i know in other states or friends with more experience, so I'm just wondering if anyone has any suggestions on what else I could possibly be doing to help or what I'm doing wrong. I just really don't want things to get worse and I just can't figure out why they aren't better at this point.

Thanks for any help..