(WLNS) – The outbreak that started at the Kellogg Center last week, has now been confirmed as Norovirus, which has affected close to 400 people.

Linda Vail with the Ingham County Health Dept. told 6 News, the report of Norovirus being the illness, was not unexpected.

“The characteristics of this outbreak, the number of people in the time span that it happened, that’s not a surprise to us,” Vail said.

There is now a confirmation of what illness affected hundreds of people, but the Health Dept. is still looking to see where and how the outbreak started.

“There are a lot of questions about what they ate, where they were, that could eventually help us narrow down potentially how the whole thing got starts,” Vail said.

With numbers climbing daily, Vail expects to see those numbers continue to grow, especially with secondary cases now being reported.

“Any time you know 375 people are sick, you know there are also more,” Vail said.

The best advice for those who have Norovirus or know someone who does, is to wash your hands regularly and take a 72-hour period to recover before returning to work or school.