If you can do this cleaning every day, even better, but if you do it once a week, it’s not bad.
If it’s still messy, make sure you do it every time you use the sponge to clean utensils used to cut raw meat, no matter where it came from.
One option is to boil the sponge in water.
Another more practical method is to microwave the very wet sponge on high power.
Roberto Wolke, a chemist, journalist for the Washington Post, and author of the books, recommends placing the sponge on a plate and heating it in the microwave for one minute, maximum.
After that time, the sponge will be sterilized.
To dry, leave it in the microwave for five minutes.