Virginia Tech scientists have provided new evidence that biofilms bacteria that adhere to surfaces and build protective coatings are at work in the survival of the human pathogen Salmonella.
One out of every six Americans becomes ill from eating contaminated food each year, with over a million illnesses caused by Salmonella bacteria, according to the Centers for Disease Control and Prevention. Finding out what makes Salmonella resistant to antibacterial measures could help curb outbreaks.
Researchers affiliated with the Fralin Life Science Institute discovered that in addition to protecting Salmonella from heat-processing and sanitizers such as bleach, biofilms preserve the bacteria in extremely dry conditions, and again when the bacteria are subjected to normal digestive processes. The study is now online in the International Journal of Food Microbiology and will appear in the April issue.
"Biofilms are an increasing problem in food processing plants serving as a potential source of contamination," said Monica Ponder, an assistant professor of Food Science and Technology in the College of Agriculture and Life Sciences. "We have discovered that Salmonella in biofilms survive on dried foods much better than previously thought, and because of this are more likely to cause disease," Ponder said.
Outbreaks of Salmonella associated with dried foods such as nuts, cereals, spices, powdered milk and pet foods have been associated with over 900 illnesses in the last five years. These foods were previously thought to be safe because the dry nature of the product stops microbial growth.
"Most people expect to find Salmonella on raw meats but don't consider that it
|Contact: Lindsay Key|