upper respiratory infection or not.

Question
Hi I recently purchased a Brazilian rainbow boa from a friend of my fathers. Its been a couple of months and we realized that every time  right before she sheds she shows symptoms of having a respiratory infection, nose bubbles, wheezing ect, however as soon as she sheds shes perfectly fine. And she eats healthy and once a week. Never refuses food. Also she has a lot of scar tissue on her nose due to previous living conditions and i thought maybe the scar tissue blocks off her airway when she sheds. Were not sure of the age but we've had her for about 3 months shes about 4.5 feet and on her 4th shed on 3 months.

Answer
I would say it has to do with the scarring on the nose, a TRUE respiratory infection does not go away and will normally kill a snake within the week. So In my opinion it is not what she has, snakes with respiratory infections bubble out the nose and mouth, have a lot of slime coming from their mouth, they will wheeze and puff terribly and wont flick their tongue and tend to open their mouth constantly.

They also tend to go off food totally, due to one not feeling good and also due to not being able to smell. I say she is fine but keep a god eye on her temps. It can take just one night of low temps to cause a snake to get ill