Disinfecting Wipes May Spread, Not Kill, Germs

June 3, 2008— -- The antibacterial wipes that have emerged as a sanitary status symbol in homes, hospitals, schools, gyms and even grocery stores may not be the ultimate answer in hygiene — and they might even spread, rather than kill, bacteria.

Researchers from the Welsh School of Pharmacy at Cardiff University in Wales tested the cleaning power of three different types of antibacterial wipes containing either traditional disinfectants, detergents or natural antimicrobial substances, such as those extracted from plants.

A team led by microbiologist Gareth Williams used the wipes to clean surfaces that had been severely contaminated with the notorious bacterium Staphylococcus aureus — including the Methicillin-resistant type known as MRSA, which has become a growing concern in hospitals.

The study, presented Tuesday at the American Society for Microbiology General Meeting in Boston, found that natural antimicrobial wipes removed the most bacteria from surfaces, while disinfectant wipes did the best job of destroying bacteria.

"Ideally, you'd want the wipes to kill what they remove," Williams said.

But researchers found that all of the dirty wipes, including those with the disinfectant, still had some bacteria remaining on them. When they were reused, the wipes just transported the bacteria to another location.

"We would recommend that one wipe is applied in one application to one surface, and then discarded," Williams said. "This is in an attempt to prevent the transfer of bacteria to different surfaces."

The conditions in the study were meant to emulate the bacteria-filled environment of a hospital intensive care unit. Health professionals aim to control the levels of potentially dangerous bacteria in these settings through disinfection — in short, the removal of as many microscopic troublemakers as possible.

But disinfection should not be confused with sterilization. Disinfection is not designed to kill all organisms, but rather to simply reduce the number of organisms on a surface, said Donna Duberg, assistant professor of clinical laboratory science at Saint Louis University in St. Louis, Mo.