There are roach droppings, saliva, and small pieces of shed skin that they leave behind when they move through your home. It turns into dust when it dries out. That dust gets into your lungs, your vents, and your rugs. It is also very bad for people with asthma or allergies. Have you ever thought about why your allergies are getting worse after you clean? That could be the reason. Try... https://pestfrog.com/how-pest-infestations-can-change-the-indoor-air-quality/