Just found out I'm allergic to dust mites!  The main species are cosmopolitan pyroglphids but I call them House dust mites. 
I've always heard of them but don't know much about them.
they are so gross - they feed on skin flakes from people and pets, and sometimes mold. 
That does sound nasty, can people see them? Or are they microscopic?
they are so small and have translucent bodies so they are barely visible to most people