People who are "allergic to dust" are typically just allergic to dust mite poop. These things are ugly, once you find them in the microscope. And they live by eating your dead skin.
First they eat
Then they excrete.
They do this all night while you sleep on your sheet.
So there's a new study that says:
Maybe you shouldn't make up your bed,
Since light and air leave dust mites dead.
kirinqueen suggests an Asian style of bed making: "with the blankets, sheets and pillows folded together, and the bed mostly uncovered."
This sounds promising, but it also sounds like more work in the morning!