My snake is about 3 years old and I haven't had any serious problems with him for the two years I've had him. I just heard a sort of noise coming from him a few hours ago. He appeared to be sneezing or coughing. After a quick look in the book "The Ball Python Manual" I feared he had a respiratory infection. The temperature in his tank has dropped a bit in the past couple of days because the ambient temperature has dropped in the room he is in. After this, I closed the windows in the room and put another lamp over his tank(I use a ceramic heater) and after 20 minutes the temperature went up to 90(it was at 80) and he stopped making that sneezing/coughing noise. He seems to be breathing fine now. He couldn't have been coughing long because I have been in and out of the room most of the day. I will keep watching for any changes, but any suggestions would be appreciated. The nearest herpetological vet is an hour away so if going to the vet isn't necessary that would be great.