Updated

A single worker at a Red Robin restaurant may have exposed up to 5,000 people to hepatitis A, warn health officials in Springfield, Mo. Immunization clinics have been set up to treat people who were at the restaurant between May 8 and 16, the News-Leader reports.

Symptoms of the liver disease include fever, fatigue, loss of appetite, and discolored urine, and although the incubation period is 28 to 30 days, affected people need to be vaccinated within 14 days of infection, warn health officials, who say this is the most serious public health crisis in the county in nearly 20 years.

Health department inspectors didn't find any violations at the restaurant and it has now been declared safe, reports KY3. "Upon being informed of the incident, the Springfield Red Robin took all safety measures to ensure the well-being of our guests and team members including arranging the inoculation of all Springfield team members," the chain said in a statement.

The News-Leader notes that the virus is typically spread via food or drinks contaminated by "even microscopic amounts" of an infected person's fecal matter.

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