Just as many parents suspect, pacifiers are a gold mine for germs, a new study shows.

The study doesn't show whether any babies got sick from their germy pacifiers.

Parents have enough to worry about without stressing about germs on pacifiers, says infectious disease specialist Bruce Hirsch, MD, of North Shore University Hospital in Manhasset, N.Y. “Germs are all around us,” he says. “Of course, they are present on pacifiers and all kinds of things, and kids are great at putting all objects in their mouths.”

The study was small, with the researchers testing 10 used pacifiers taken from healthy infants, and seven new pacifiers. Five of the used pacifiers were slightly contaminated, and the other five were heavily contaminated with Staphylococcus aureus, Klebsiella pneumonia, and fungus. In all, the researchers found more than 40 different species of bacteria on the pacifiers.

New pacifiers also had bacteria, but not as much. “They don’t have as much because they are not exposed to food and water yet,” says researcher Thomas Glass, DDS, PhD. He is a microbiology expert at Oklahoma State University Center for Health Sciences in Tulsa.

The study was not designed to see if kids became sick from using the pacifiers.

The findings will be presented at the 2012 American Society for Clinical Pathology annual meeting in Boston.

How to Clean a Pacifier

If your child uses a pacifier, sanitize them each evening, Glass says: “Sanitizing them can reduce the number of organisms and prevent biofilm from forming.”

He suggests how: Use a denture solution, which you can buy without a prescription, and soak three of four pacifiers overnight. “Wash them off and put them in a bag,” Glass says.

Pacifiers are not meant to be used indefinitely, either. Glass recommends all used pacifiers be thrown out after two weeks. If your child is sick, replace all their pacifiers.  “Pacifiers can become a reservoir, so if your infant becomes ill, throw away all pacifiers and start with new ones.”

Also, if a pacifier falls on the floor, don’t pick it up and put it back in the baby's mouth, Glass says. 

Not everyone agrees with these precautions.

"A dirty pacifier may be a good thing,” Hirsch says. “Exposure to multiple types of bacteria early on in life can help an infant develop and sustain a healthy immune system."

These findings were presented at a medical conference. They should be considered preliminary as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.

SOURCES: Bruce Hirsch, MD, North Shore University Hospital, Manhasset, N.Y.Thomas Glass, DDS, PhD, professor of forensic sciences, pathology, and dental medicine;  adjunct professor, microbiology, Oklahoma State University Center for Health Sciences, Tulsa.American Society for Clinical Pathology annual meeting, Boston, Mass. Oct. 31-Nov. 3, 2012.

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