Health officials offered free shots Tuesday to anyone potentially exposed at the Waffle House in Clinton from April 5 to April 15, when the restaurant estimates it served as many as 5,000 people.
Dr. Paul Erwin, director of the regional health office, said the infected employee was a victim of the outbreak.
Seventeen cases of hepatitis A, a viral liver disease that can be spread through poor hygiene, have been confirmed in recent weeks. Two people were hospitalized.
Officials suspect all were infected at a LaFollette restaurant in March, but no employees at that restaurant or any other in Campbell County have tested positive. It can take up to a month before an exposed person becomes sick.
"Unfortunately, because it covers such a large block of time, they (the victims) have eaten at several restaurants," said health office spokeswoman Carole Martin.