Toothbrushes May Be Source of Pneumonia, Diarrhea and Strep Throat


Sara Frock of New Haven, Ind., says her family changes toothbrushes once a year when the dentist gives them new brushes at an annual visit. Waunita Lauder of Palmdale, Calif., says her husband changes his toothbrush when it gets bent out of shape because he is concerned about his gums and wants to avoid plaque and tartar buildup.

Waiting until a toothbrush is worn out may not only affect dental health, it can have an effect on health, as well.

The problem is, the toothbrush on the bathroom counter may be home to a lot more than the latest tartar-control toothpaste. At least one study shows that bacteria and yeast associated with pneumonia, stomach ulcers, strep throat, sinus disease, upset stomach and diarrhea are often found on well-used brushes.

“It’s like using the same piece of dental floss for 6 months,” said Donald Duperon, professor of pediatric dentistry at the UCLA School of Dentistry.


Studies conducted at the University of Oklahoma showed that a herpes virus could live for 48 hours on a dry toothbrush. When the brush was wet, the virus lived for as long as 7 weeks.

“There’s no telling how long some viruses can live on a wet toothbrush in a bathroom.” said Tom Glass, professor of oral pathology at the Colleges of Dentistry and Medicine--and principal investigator in the toothbrush studies--at the University of Oklahoma.

Bacteria and viruses thrive where there is food and water, making toothbrushes a vulnerable target. When the virus is present, all that is needed for possible infection is a port of entry. A slight scratch by a toothbrush may be all it takes.

And the bacteria associated with pneumonia, strep throat, diarrhea and other illnesses that the researchers found lurking on toothbrushes weren’t necessarily there because the toothbrush user had contaminated his own brush. The bathroom itself was thought to be the culprit.


“The bathroom is by far the most unsanitary room in the house. When someone flushes the toilet, those germs aerate all over the bathroom” Glass said.

Keeping the cover of the toilet down when not in use may help prevent the spread of germs. But, according to Glass, what is really needed is a whole overhaul of the bathroom.

“We’re advocating to vacate the bathroom of everything except soap, toilet paper and towels.” said Glass. He suggests that the toothbrush be kept in a cup in the bedroom, along with a small tube of toothpaste.

Both Glass and Duperon agreed that family sharing of toothpaste is not a healthy habit. When one person strikes his brush to the pump or tube, it can leave behind germs for the next user.

The toothbrush should be kept as dry and clean as possible. It may also be worthwhile to dip the brush in antiseptic mouthwash, said Duperon, and then shake it. Having separate brushes for morning and evening, he said, may cut down on the amount of germs on each brush.

And changing toothbrushes once every 6 months or year is not enough. Healthy people, Glass said, should probably switch brushes about once a month, while people with immune disorders should do so much more frequently.

When suffering from a cold, a brush should be changed at the very first sign of recovery to avoid re-infection. Glass’ studies showed that cold germs can remain on a toothbrush for up to a month. As soon as the cold sufferer begins to feel completely well, a new brush should be substituted.

And the toothbrush should not be seen as a friend to which one becomes attached.


Although children are often taught differently, the toothbrush is merely a hygienic tool and should be disposed of like any other hygienic tool, said Glass, who is developing hygienic and disposable toothbrushes.

“We’ve done a good job socially of making toothbrushes our friends,” he said. “Who wants to get rid of a friend? But it’s only a hygienic device--nothing more, nothing less--that’s the key.”