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Dishwashing doesn't nix norovirus

December 14, 2012

NORWALK, CT — A new study suggests that commercial dishwashers can kill everyday bacteria, but not the winter vomiting bug known as  norovirus, according to HealthDay News.

commercial dishwasherResearchers from Ohio State University found that, while restaurant industry guidelines for cleaning dishes and silverware eliminate bacteria, they are not effective against norovirus, as the virus has been found to withstand both manual and mechanical washing, the article stated.

"We know that, when public food establishments follow the cleaning protocols, they do a very good job at getting rid of bacteria," said study leader Melvin Pascall, associate professor in the department of food science and technology.

"Now, we can see that the protocols are less effective at removing and killing viruses, and this may help explain why there are still so many illnesses caused by cross-contaminated food," Pascall added.

According to the article, researchers contaminated cream cheese and reduced-fat milk with a norovirus, Escherichia coli (E. coli) or Listeria, three common causes of foodborne illness; the utensils were washed by hand or in a dishwasher following sanitizing protocols that used chlorine and quaternary ammonium compounds (quats).

While both handwashing and dishwashers reduced E. coli and Listeria to safe levels, neither cleaning method could reduce the presence of norovirus, the article noted.

Click here to read the article in its entirety.