dust mite

First, Fassett removed the IL-31 gene from mice and exposed them to the house dust mite, a common, itchy allergen.

"As we expected, the dust mite didn't cause itching in the absence of IL-31, but we were surprised to see that inflammation went up."

Three tablets treat grass or ragweed allergies, and a fourth gained approval in 2017 for dust mite allergies.

“Household dust is a complex matrix of components including dust mites, dust mite feces, bacteria, mold, pet dander, small insects, pollen and particles,” Ketan Patel, design manager of floor care at Dyson, told Better Homes & Gardens.

“Dust mite droppings, dead bodies of dust mites, pet dander, and small insects are included as allergens.”