While you likely clean your toilet regularly, you might be neglecting to clean the brush. The brush can harbor germs and mold, but there is a simple way to clean it.
After cleaning your toilet, @acleanbee suggests pouring bleach into the bowl and setting the brush inside for one to two hours. Afterward, hang the brush over the bowl to dry.
However, putting bleach in the toilet can damage the inside of your toilet and cause it to leak. Instead, you can use natural cleaners like vinegar as a safer option.
Alternatively, the user suggests heavily spraying the brush with an alcoholic cleaner, letting it dry over the bowl, rinsing it with hot water, and leaving it to dry.
Another method is to wash the brush with the water of the cleaned toilet. Place your brush in the toilet bowl, and flush it, allowing the pressure to remove the debris.
If you want to use bleach but are worried about damaging your toilet, you can clean the brush in a bucket with 1 cup of bleach and 3 quarts of hot water.