It probably goes without saying, but it’s always a good idea to keep the inside of your home clean. If not for health and sanitation purposes, then definitely for the visual appeal of a neat and tidy home, especially if you’re expecting visitors! However, while you may do a great job of cleaning up the mess you can see, it’s the invisible sources of uncleanliness that are often the most insidious.
In this case, they could be in your indoor air.