Detecting foodborne illness in restaurants

RICHMOND, VA (WWBT) - Last month, 30 hospital workers caught the norovirus at Bon Secours St. Francis Medical Center in Chesterfield. The Chesterfield Health Director said among the possible sources was a catered employee-recognition event.

Then doctors on the Explorer of the Seas cruise ship suspected norovirus is what made 600 passengers sick last month. No word yet on what the source was.

We often hear about illness outbreaks in the news, but we don't often hear about foodborne illness in restaurants.

Every Thursday, our Restaurant Report shows you critical violations local restaurants make on health inspections, but you won't find foodborne illness complaints in inspection reports.

Under the Freedom of Information Act, we obtained the records on what the Virginia Health Department says were four foodborne illness outbreaks in Central Virginia restaurants and facilities last year.

But they came with a disclaimer from the Health Department: "It is often very difficult to identify whether an outbreak is truly due to foodborne transmission, or if the pathogen could have spread person to person."

So why is so difficult? The Health Department let us inside. When they hear someone is sick, they contact the restaurant and customers and collect a history of everything they ate over the last few days.

State Epidemiologist Dr. David Trump says they start asking questions, "When people got sick, what foods they ate, who didn't get sick."

Once a foodborne illness is suspected, they'll take samples from the possible food source and stool samples from the people who got sick, and they'll bring them to the Division of Consolidated Laboratory Services in Richmond.

The lab determines whether the problem is a bacteria, like salmonella or E-coli, or a virus, like norovirus, and the possible food source.

"Could it be a jar of peanut butter that was nationally distributed? Or it could be a food handler that was working at a restaurant and was ill?" Lab Deputy Director Dr. Denise Toney told us.

Here's why they say its difficult to pinpoint the source.

"We know at a buffet, people eat different stuff," explained Dr. Trump. "We never have laboratory testing on everybody. We never have the perfect symptoms on everybody."

"You're relying on individuals to remember what they ate, or where they had visited," added Dr. Toney. "It can be two to three days before an individual can become sick."

Norovirus can be spread both person-to-person, or through food. They say food transmission of norovirus is particularly hard to detect because there may only be a few particles of the virus on one part of the food.

"As you can imagine, the infectious dose is very low, anywhere form one to ten viral particles," said Dr. Toney. "So to try to find that low level of virus in a food sample is very difficult."

The Health Department immediately helps the restaurant stop the outbreak. And the good news is that foodborne illness in Virginia restaurants is pretty rare.

Said Dr. Trump, "On average we have about twenty across the state. Twenty foodborne illness outbreak investigations per year that we really feel pretty comfortable are food related."

So how can you help protect your family when you eat out? Check the restaurant inspection reports for repeated critical violations. Note foods that aren't as hot or cold as they should be. And watch for chefs or food servers that appear sick.

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