TORONTO - Antibacterial wipes used in hospitals may not be having the intended effect, a new study from Wales suggests.
The work, done by researchers from Cardiff University's School of Pharmacy, shows that the wipes do not kill high numbers of Staphylococcus aureus bacteria. So if they are used on more than one surface, rather than cleaning they may just be spreading germs around.
The researchers studied three types of wipes - one containing detergent, another containing disinfectants and a third containing a natural antimicrobial product.
"We found that all three wipes suffered from the same problem, in that they transferred high numbers (of bacteria) and in fact in most cases uncountable numbers to consecutive surfaces. ... Too many to count to the consecutive surfaces," said Gareth Williams, a microbiologist who presented the findings Tuesday at an American Society for Microbiology conference in Boston.
Williams wouldn't name the products and it's unclear if they would be used in Canadian hospitals.
But he said the work shows there's a risk in using similar products if a single wipe is used to clean more than one surface.
Dr. Andrew Simor, head of microbiology at Toronto's Sunnybrook Health Sciences Centre, said he wasn't surprised by the findings.
"These disinfectants don't kill all the bugs. That's not how they work," said Simor, who was not involved in the research.
"You're physically removing a layer of the organisms. But that doesn't necessarily kill them. And so it's easy to pick them up and transfer them to another area."
Simor said in North America infection control recommendations would specify that a wipe should be used to clean a single area and then should be discarded.
Williams and his colleagues started their work by watching how cleaners in an intensive-care unit used the products.
"There was a tendency for the staff in the intensive-care unit to ... move on to consecutive surfaces in close proximity to the initial surface. So from a bed rail to a table, for instance. ... With the same wipe."
"That set the alarm bells ringing."
They tested whether the three types of wipes could transfer methicillin-resistant Staph aureus - MRSA - or the antibiotic sensitive form of the bacteria from a surface inoculated with the bugs and whether the germs died if they were directly applied to the wipes.
All three types transferred MRSA, though in differing amounts. And none killed sufficient quantities of the bacteria to make reuse of a wipe safe.
Williams said his group is writing guidelines to make clear these products should be used on a single surface only.
The researchers did not study whether the same effect would be seen in a household if, for instance, a single wipe was used to clean multiple surfaces.
But Simor said in his estimation these types of products aren't needed in homes.
"Our households are not settings where you've got the same risk of spread of infection from the environment to individuals (as in hospitals)," he said. "The germs that are involved are generally not as virulent or not as capable of causing such severe disease."
"And finally, standard good household practices are really all that's required to make a household kitchen or bathroom or bedroom safe. You don't need all this other stuff."
