The latest Vital Signs report from the Centers for Disease Control and Prevention indicated this week that most norovirus outbreaks originate in restaurants and other similar establishments. In specific, the report suggests that infected restaurant employees are the typical source of norovirus outbreaks due to their touching ready-to-eat foods with their hands, resulting in what is colloquially known as the “stomach flu.” Ready-to-eat foods are defined as foods that do not require extra preparation, with examples of such foods including washed raw fruits and vegetables, as well as raw oysters and baked goods. According to CDC director Dr. Tom Frieden, most individuals learn about norovirus from its reputation as a leading cause of stomach flu outbreaks on cruise ships. He noted, however, that those cruise ship outbreaks only take up about one percent of all reported norovirus outbreaks. The virus can cause outbreaks in any situation where people are together, with food being served. The CDC claims that the most common way norovirus is spread is direct person-to-person contamination, while the second-most common route of transmission is foodborne transmission. “Norovirus outbreaks from contaminated food in restaurants are far too common,” said the CDC’s Frieden, stressing the importance of preventing outbreaks from happening whenever possible. “All who prepare food, especially the food service industry, can do more to create a work environment that promotes food safety and ensures that workers adhere to food safety laws and regulations that are already in place.” The CDC provided a list of guidelines that could be used by food service companies to prevent norovirus outbreaks. These include providing proper training and tools to food service workers and giving food safety certifications to kitchen managers, ensuring that food service workers always wash their hands properly and only use disposable gloves and utensils, and requiring workers to stay home for at least 48 hours following the cessation of symptoms such as vomiting and diarrhea. The last guideline was a particular pain point for report co-author Aron Hall, who stressed on the report that businesses “consider using measures that would encourage sick workers to stay home, such as paid sick leave and a staffing plan that includes on-call workers.” Four years of data was included in the CDC’s analytic study, though it did primarily center on foodborne outbreaks. Among these outbreaks, 520 were due to food contamination in some way, shape, or form, with 70 percent of the cases pinning the blame on infected food service workers. Out of that 70 percent, 54 percent of those cases were related to food workers handling ready-to-eat foods with their own hands. Out of the total 324 norovirus outbreaks which had a food item implicated, more than 90 percent of the items had gotten contaminated in the final stage of preparation, and about three-fourths (75 percent) of those cases were connected to raw foods. Fruits, leafy vegetables, and molluscs (e.g. oysters) were the specific types of raw food most commonly associated with norovirus outbreaks.