More than 90 people in Hartford City, IN have been sickened, and two were hospitalized, in an outbreak of norovirus traced this week to a Subway restaurant, according to the Blackford County Health Department.

According to news reports, the sheriff’s department began receiving calls Saturday concerning the illnesses.

Following an investigation that included the Indiana Board of Health, a Subway restaurant agreed to close on Tuesday. It reopened Friday and “we are confident that the local food establishment has properly addressed the situation,” Linda Briles, registered environmental health specialist with the Blackford County Health Department, said in a news release.

Briles said the contamination was “traced to a human,” but declined to elaborate until the state issues a report, the Muncie Free Press reported.

A separate norovirus outbreak in Northwest Indiana has been linked to a Jimmy John’s restaurant in Valparaiso.

Noroviruses, the leading cause of foodborne illness in the United States, are found in the stool and vomit of infected people, who can be exposed through contaminated foods or liquids; touching contaminated surfaces or objects, and then placing their hand in their mouth; or direct contact with an infected person; for example, sharing food, drinks, or eating utensils with an infected person.

Norovirus outbreaks occur throughout the year, but more than 80 percent of them occur from November to April.