Do You Really Need to Toss Toothbrush After a Sore Throat?

There’s an old wives’ tale that after suffering from a cold, the flu, strep throat or a sore throat, you need to toss your toothbrush.

According to a study presented at the Pediatric Academic Societies (PAS) annual meeting in Washington, DC, when it comes to sore throats, there’s no reason to discard your old toothbrush.

However, should you still toss your toothbrush when you have strep throat?  There are those health care professionals who do advise their patients to toss their toothbrushes after a bout of strep throat. Researchers from the University of Texas Medical Branch (UTMB) at Galveston decided to conduct a study to discover whether or not this advice was true.

The first step in the study was an attempt by researchers to grow group A Streptococcus (GAS), which is the bacteria that causes strep throat, on toothbrushes.  The researchers discovered that GAS did grow and remain on the toothbrushes for 48 hours.

Two new toothbrushes that were not exposed to GAS and served as controls surprised researchers by growing other types of bacteria even though they were sterile when removed from their packaging.  Because the toothbrushes, an adult-sized and child-sized brush, grew other types of bacteria, these findings were not investigated further by the research team.

The second step in the study was to discover whether GAS would grow on toothbrushes used by children who had strep throat.  In the study group aged 2 to 20 years, fourteen patients had strep throat, thirteen patients had sore throats without strep and twenty-seven patients were well.  These patients brushed their teeth with a new toothbrush for one minute, and then the toothbrushes were placed in a sterile cover and taken to a lab to be tested for GAS growth.

Researchers were surprised that GAS grew on only one toothbrush, a toothbrush used by a patient without strep throat.  All other toothbrushes used in the study failed to grow GAS; however, they did grow common mouth bacteria.

Judith L. Rowen, MD, Associate Professor of Pediatrics in the Dept. of Pediatrics at UTMB, and co-author of the study said, “This study supports that it is probably unnecessary to throw away your toothbrush after a diagnosis of strep throat.”

Dr. Rowen’s co-author, Lauren K. Shepard, DO, however commented that because the study was so small, larger studies will be needed to confirm that GAS does not grow on toothbrushes used at home by children with strep throat.