Kids in day care centers could be sharing more than just toys when they’re passed around.
Two bacteria that cause some of the most common infections in children survive on objects and surfaces much longer than previously thought, according to a team of University at Buffalo researchers.
Streptococcus pneumoniae, a cause of ear and respiratory infections, and streptococcus pyogenes, the cause of strep throat and skin infections, were thought to die rapidly soon after leaving the human body.
But strains were found in a day care on hard-to-clean items such as stuffed toys and books many hours after kids had any contact with them, according to the study published last week in the journal Infection and Immunity.
“This would indicate that there is a potential for spread, that this is a way these bacteria could possibly spread between individuals,” said lead author Anders Hakansson. “How much that occurs, we don’t really know.”
Hakansson, a UB assistant professor of microbiology and immunology in the School of Medicine and Biomedical Sciences, and doctoral students Laura R. Marks and Ryan M. Reddinger used their previous research to answer why their findings went against conventional wisdom.
Bacteria that infect people have a hearty, protective matrix known as “biofilms,” which are not found on bacteria used in laboratory research, he said.
“When people have worked with those in the past, they have just seen how they survive when grown under laboratory conditions,” he said. “They’ve never been interested in biofilms because they didn’t really know that they made biofilms.”
The researchers found that while laboratory-grown bacteria on plastic died within a day, streptococcus pneumoniae and streptococcus pyogenes with biofilms survived for a month and three months, respectively.
“They actually survived for a very long time, much longer than we thought,” Hakansson said.
They also found that biofilm bacteria survived for hours on hands despite the skin’s natural antimicrobial agents, while laboratory bacteria died almost immediately.
“We went one step further and we thought, ‘OK, if we go to a day care can we find these bacteria on inanimate surfaces even long after the kids have gone home?’ ” Hakansson asked.
They did – which could have far-reaching ramifications for cleaning guidelines in places including day care centers and hospitals. For example, the Centers for Disease Control and Prevention does not worry about infection through surface contact with pneumoniae and pyogenes, Hakansson said.
“But maybe that is not really true, with the new knowledge that we have,” he said.
While it is too early to make specific recommendations, Hakansson said standard practices such as wiping down surfaces with hot water and soap and good hand-washing are essential.
“Washing hands is extremely important,” he said. “I think that’s what I would press for most.”