What's the dirtiest spot in the bathroom? (Hint, it's not the toilet.) The bathtub, shower curtain, sink and even your toothbrush and toothbrush holder harbor tons of bacteria - and don't receive the same scouring your commode does. Disinfect the entire bathroom once a week with an antibacterial cleaner or a bleach solution. Also, change your shower curtain liner regularly, spritz your bathtub basin and tiles daily with a shower cleaner and replace your toothbrush once a month (or after you've gotten over a cold).