too much sneezing...

[peck]

hello guys,
my new hamster(3 months) and his brothers cough too much.
Their cough began a long time ago. (maybe 1month)
They hardly cough when they are sleeping and running.
The symptoms are the same for him and his brothers.

we had go to many vets(more than 6), but even they don't know reason...
vets said it's not cold, flu, and allergies.

so I need your help
Is this an inherited disease???
if you had some situation like this, or have some advise, please tell me.
thank you.

[Careba]

Do you have some kind of air freshener in the room the hamsters are in? They have very sensitive lungs, so if there is any perfume or sprays or even one of those fresheners you plug in, it could be affecting them.

[cypher]

It's hard to say without knowing more, as Careba says it could be anything strongly scented in the room or close by, what substrate & food do you use? What about cleaning the cage, do you use any scented products, disinfectants, powders or anything that could cause a problem?
What do you feed them? That could be an issue too possibly.

[BubbyandHamper]

Hamsters are very sensitive to fragrances and it can stress them out, cause sneezing, or even make them ill! You should probably remove and fragrant items from their room and cages because that can be an issue.

[Jeir]

Substrate may also be a cause. My last bag of Fitch ended up being super-dusty, and my Syrian sneezed a lot when he was on it. New bag and he's fine.