[greg_V]

Anecdotal backup: as a child I had a horrendous dust allergy that led to multiple hospital visits. To mitigate the problem, my mom became a clean freak, trying to keep our apartment dust-free. The allergy persisted until I grew up and moved out on my own without having a vacuum cleaner. Living in a messier environment led to the allergy basically disappearing.

[makeitdouble]

Could it have been an allergy to something other than dust ?

I have an allergy to a specific cleaning product ingredient for instance, although I never got to know what exactly. It was not something commonly used, I never triggered it by myself and only reacted when helping cleaning a friend's house decades ago.

My kid also seems to have it, but again it only ever happened once at a shop, and no allergy test raised it (other stuff were found though)

"dust" allergy is sometimes complicated.

[ajuc]

Counter-anegdote. I grew up in the countryside, I am allergic to hay, pollen, dust mites, cat and horse saliva, and more.

I moved to a big city when I was ~20 and my symptoms got better, but I'm still allergic to all that - it's simply not putting me in hospital anymore.

Doctors told me most people grew out of the worst symptoms over time.

BTW I also somehow got allergic to kiwi fruits between primary school and my late 20s. I ate them rarely and at one point I found out they make me throat swell like a balloon. Didnt' happened before.