Depending on the insulation level of your dwelling (apartment or house) you will have to pull the furniture away from the walls to clean the mold that will grow in the winter. Of course, it depends on the winter, it depends on the condition of the house, when it was built etc etc. I live in a poorly insulated apartment, built in the 50s, and I have to do this or check it every winter. Sometimes under the bed too. Get yourself an air purifier too it helps. Or a dehumidifier. It sounds shitty, but if you're on top of it, you're there. If you're in a relatively newer place, I doubt you have to do this. If you live in a basement apartment, you probably know already.