I must admit, in 30 years of doing food safety, I seldom recall a health department withholding from the public the source of an outbreak – even Norovirus.

I am reminded by a story some 10 years ago – After Food Safety News broke the story that Taco Bell was the mysterious “Restaurant Chain A” linked to a Salmonella outbreak that sickened 68 people in 10 states, ABC Evening News praised Food Safety News for shining light on this story and the issue of the government’s lack of transparency when businesses make people sick.  Other media, such as the LA Times, Reuters, Daily Mail, The Consumerist, CBS News,Huffington Post, Fox News, and MSNBC, also hailed Food Safety News for shinning the light on the mystery taco restaurant.  Most recently, Barry Estabrook wrote a piece for The Atlantic detailing Food Safety New’s muckraking skills, but praised me and not the people who did all the work.

The San Luis Obispo Tribune reports that an outbreak of norovirus stemming from a North County restaurant has sickened close to 100 people, according to the San Luis Obispo County Public Health Department. SLO County Public Health Epidemiologist Jessie Burmester said 97 people have been reported sick as part of a confirmed norovirus outbreak earlier this month. Burmester said the Public Health Department traced the “unusual, very large community outbreak” back to a North County restaurant, though she did not disclose the name of the business.

“When we perform our investigations, we’re really looking for a common source or exposure point,” she said. “Individuals have provided the name of the restaurant consistently for all the individuals that have reported on behalf of the 97 people so far.” Burmester said the Public Health Department reached its threshold for an outbreak — two reported cases in separate households — on May 15. That day, the agency received more than two reports about the same exposure source, she said. Follow-up investigation showed some people experiencing symptoms of norovirus tied to that facility as early as May 11, Burmester added.

Once it was identified, the Public Health Department began working to help eliminate further spread by pushing “mass cleaning and disinfection” of the restaurant, as well as attempting to track where the cases originated. The restaurant in question has been cleaned three times since the outbreak was first reported, she said. “This has been particularly challenging outbreak,” Burmester said, “but it is not abnormal to see norovirus spread like this, because it doesn’t take much of the virus to spread at all.”

Norovirus is a nasty bug.

Noroviruses are estimated to cause 23 million cases of acute gastroenteritis (commonly called the “stomach flu”) in the U.S. each year, and are the leading cause of gastroenteritis. In addition, norovirus outbreaks may be the most common foodborne illness outbreaks. Noroviruses can cause extended outbreaks because of their high infectivity, persistence in the environment, resistance to common disinfectants, and difficulty in controlling their transmission through routine sanitary measures.

The norovirus is transmitted primarily through the fecal-oral route and fewer than 100 norovirus particles are said to be needed to cause infection. Transmission occurs either person-to-person or through contamination of food or water. Transmission can occur by:

· Touching surfaces or objects contaminated with norovirus and then placing that hand in your mouth

· Having direct contact with another person who is infected with norovirus and showing symptoms

· Sharing foods or eating utensils with someone who is ill

· Exposure to aerosolized vomit

· Consuming food contaminated by an infected food handler.