Norovirus Survives Restaurant Dishwashing Protocols

December 21, 2012

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Thinking of eating out over the holidays? Well, you might consider bringing your own plate. Because a new study shows that the typical dishwashing procedures used by most restaurants can’t wash away viruses that can cause some serious stomach distress. Those unsavory findings are served up in the journal PLoS ONE. [Lizanel Feliciano et al., Efficacies of Sodium Hypochlorite and Quaternary Ammonium Sanitizers for Reduction of Norovirus and Selected Bacteria during Ware-Washing Operations]

Food poisoning is no fun. And one potential source of sickness when you dine out is the dinnerware. Plates, forks, and glasses could transfer a bug from contaminated foodstuff or a previous diner to you. Most public eateries follow certain industry guidelines when it comes to cleaning their tableware. But those protocols were designed with foodborne bacteria in mind. So what happens if the infectious agent is viral?

To find out, researchers inoculated cream cheese and milk with either E. coli bacteria or a norovirus, famous for spreading throughout cruise ships. The researchers shmeared the mess over ceramic plates, utensils and glassware…and then put the dirty dishes in the wash. And they found that while the standard detergents did a decent job at sluicing away the E. coli, they didn’t get rid of the dairy-encrusted virus.

So bon appetit.  And caveat emptor.—Karen Hopkin

[The above text is a transcript of this podcast.]

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