Penn State University researchers have developed a test that cuts in half the time it takes to determine the exact strain of Salmonella involved in a foodborne illness outbreak.
The technique also could be applied to other organisms, such as Campylobacter and E. coli.
The test typically used, pulse field gel electrophoresis or PGFE, typically taktes one to three days to identify the specific strain, according to a news release.
The new technique could take as little as one day.
"The significance of that is you need to trace the source of an outbreak as quickly as you can before you start insisting on restaurant and farm closures," study lead author Nikki Shariat, postdoctoral researcher in molecular microbiology, said in the release. "It is important to pinpoint the source of the bacteria—the quicker you do that the quicker you can respond to the disease outbreak."
The method focuses on two genes that cause virulence and two novel regions within the Salmonella DNA.
The scientists developed a method of typing that can detect strain-specific differences in the DNA in the four locations.
Their method looks at the DNA sequence compared with earlier methods that cut the DNA into small pieces with no actual sequence information.
They used the Salmonella serotype Newport, which is the third most common variant of Salmonella and accounted for 9.3 percent of total salmonellosis cases in 2009.