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01:09 - Source: CNN
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Restaurant workers who handle food while they are ill are among the leading drivers of foodborne illness outbreaks at restaurants, according to a new study from the US Centers for Disease Control and Prevention.

The study, which was published Tuesday in the CDC’s Morbidity and Mortality Weekly Report, covers 800 outbreaks of foodborne illness at US restaurants between 2017 and 2019, reported by 25 state and local health departments.

The most common pathogens identified were norovirus in almost half of the outbreaks (47%), followed by salmonella (19%).

Norovirus, which is often associated with cruise ships for the misery it has caused for passengers at sea, is highly contagious and causes vomiting and diarrhea about two days after infection. Salmonella bacteria cause diarrheal illnesses that start two to three days after contact. Salmonella may also cause abdominal cramps, infection, chills, nausea and vomiting.

Contributing factors were identified in about two-thirds of restaurant-related outbreaks of foodborne illnesses. Among these, 41% were related to workers handling and contaminating food while ill.

While most restaurants surveyed for the study had policies aimed at keeping sick staff from working, fewer than half (44%) offered paid sick leave. The study authors say that extending paid sick leave for more restaurant workers could curb food contamination by safeguarding income for restaurant workers who typically work for low hourly wages and tips.

“This issue illustrates very clearly how the health of workers and consumers is connected. Everyone benefits when sick workers are allowed to stay home,” said Sarah Sorscher, director of regulatory affairs at the Center for Science in the Public Interest in Washington, DC.

The study also pointed to communication gaps between restaurants and workers. While most restaurants had written policies requiring staff to tell their managers when they were ill and highlighted the need to report certain symptoms, only a minority (23%) specified all five symptoms that should keep someone home from work: vomiting, diarrhea, a wound with pus, a sore throat with a fever, or jaundice.

Only 16% of restaurants involved in outbreaks clearly communicated and followed through on four key recommendations: They had a policy that sick staff should tell a manager when they’re not feeling well, staff were urged to report illness any time they had any one of five risky symptoms, the restaurant didn’t allow workers to work while ill, and workers had been told about all five symptoms that should keep them home from work.

The CDC says more comprehensive food safety policies could also cut down on contamination.

“Obviously, encouraging employees who are clearly sick to stay home is good policy. Whether or not they do that, when they’re facing the possibility of not getting a paycheck may be an issue, especially if they’re not that sick yet,” says Bill Marler, a Seattle attorney who specializes in cases related to foodborne illness.

Although expanding access to paid sick leave is important, he said, it probably wouldn’t stop all worker-associated outbreaks, because people often become contagious before they’re aware they are ill.

“There’s a significant minority of cases where people are asymptomatic,” he said.

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“So they’re coming to work and they don’t know they’re sick at all, and they’re transmitting salmonella or norovirus, or they’re at the very beginnings of their illness” and so not sick enough to stay home, Marler said.

Marler says one proactive thing that the CDC could do is to recommend hepatitis A vaccinations for restaurant workers.

Hepatitis A accounted for just three outbreaks out of 555 in the new report, but Marler says these outbreaks can be extremely consequential.

He says he had a case out of Roanoke, Virginia, from 2021, when hepatitis A at a restaurant sickened 50 people. At least one person died, and two needed liver transplants, Marler said. Two of three restaurants involved in the outbreak filed for bankruptcy.

Cases like these could be prevented, he said, if more restaurant workers were vaccinated.

Correction: After this story was published, the CDC corrected the number of restaurants in its report.