"It looks like the bacteria multiply either on the floor of the kitchen, or I suspect people don't clean their dog bowls," said Pfanner, who was not involved in the study.
On the other hand, the researchers found that children who actually put pet food into their mouth seemed to have no added risk.
The Pennsylvania plant where the contaminated pet food was manufactured was eventually closed, the researchers note. However, they add that since 2006, at least 135 pet products, including pet supplements and pigs' ears, have been recalled as a result of Salmonella contamination.
This new study, "re-emphasizes the importance of washing your hands whenever you deal with anything from a pet, including petting him, touching his mouth or cleaning up after him, especially for children whose immune systems are very weak in comparison to adults," said Dr. Philip Tierno, clinical professor of microbiology and pathology at New York University Langone Medical Center in New York City and author of The Secret Life of Germs.
"Hand washing is the single most important thing anyone can do to protect their health, and that's within everyone's purview if you teach them," Tierno said. "You can do that and not be afraid."
Another precaution is to have well-packaged, well-stored pet food, keeping it out of the reach of infants and toddlers, said Richel.
"This is a small section of total cases of Salmonella, but it's important because so many of our kids are on the floor all the time," said Pfanner.
The U.S. Centers for Disease Control and Prevention has more on Salmonella.
SOURCES: Timothy Pfanner, M.D., assistant professor of internal medicine, Texas A&M Health Science Center College of Medicine, an
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