I have had several bad colds recently. My physician said that I may be reinfecting myself when I use my toothbrush. Kim Loos, DDS Dr. Kimberly A. Loos practices general dentistry in San Jose, California. She is also a clinical instructor at University of Pacific School of Dentistry and an editor for Dentistry On-Line.
Toothbrushes can harbor bacteria, viruses, and other disease-causing organisms.
Toothbrushes can also become contaminated with saliva and blood. In fact, the parainfluenza virus can survive on toothbrush bristles for over 24 hours. Atmore et al. Your brush is most likely to act as a disease vector if you share it with another person or if the brush is not permitted to dry completely after each use. Most bacteria thrive in warm, moist environments.