One of my many obsessive compulsive traits is the wringing and disposal of kitchen sponges. Unless sponges and dishcloths are replaced, laundered or disinfected regularly, they provide a breeding ground for microbes that make a home in their pores. These microbes use food residues for their growth. Within a week of use, the sponge may contain billions of bacteria, as evidenced by its smell (moldy feet) and feel (chalky hamster). If we use such a sponge for wiping surfaces, we are spreading bacteria. If the sponge is contaminated with pathogenic bacteria, spreading them makes it easier for other people to pick up the contamination and possibly become ill.