If you prefer to use sponges to clean with instead of cloth: Sanitizing your sponge every time you use it is a must. You need to guard against cross contamination.. While testing common household methods used to disinfect sponges, researchers at the USDA found that over 99 percent of bacteria, yeasts and molds were killed by microwave heating damp sponges for one minute or dishwashing with a drying cycle. Sponges may also be disinfected with a solution of one-quarter to one-half of a teaspoon of concentrated bleach per quart of warm water. Soak the sponge for one minute. Replace your sponges frequently.