CHICAGO (CBS) – About 15 kindergarteners from a Chicago Catholic school became ill after visiting the Shedd Aquarium.

This report comes two weeks before Andrew High School students reported being sick after attending prom at the Shedd.

According to Archdiocese spokeswoman, Anne Maselli, 52 students from St. Clements were in the group of kindergarteners that visited the Shedd Aquarium on April 17. She says the students did not eat there.

The students report having the same Norovirus symptoms that more than 100 Andrew High School students also reported.

Health officials have not identified the source of what is causing kids to get sick, but say their symptoms are consistent with Norovirus.

The Shedd Aquarium, Department of Public Health, food services, and the schools are working together to investigate this issue.

The Cook County Health Department says there is no update regarding the investigation at this time.

A Shedd Aquarium spokesperson says, the Shedd has hosted several large private catering events in the past few days, including another large prom Saturday night and says there are no reports of illness from those events.

The Chicago Shedd Aquarium released a statement saying, “The care and well-being of our guests is always a top priority. As such, we took it upon ourselves to perform several extra precautionary measures over the last few days to continue to ensure a safe and healthy place to work and visit. This included an additional deep sanitation of all areas of the aquarium, an internal review of all food preparation, service processes and environmental cleaning procedures, and a proactive invitation to public health inspectors whom we’ve welcomed onsite multiple times with open-access to all spaces.

The Chicago Department of Public Health informed us that there are no outstanding violations to any of our catering or restaurant facilities and no restrictions to operations. We will continue to work in close partnership with city, county and state officials on any inquiry. There are no reports of illness from subsequent large private catering events held at Shedd, including another large prom held Saturday evening. In addition, Shedd Aquarium and the Chicago Department of Public Health have received no reports of similar symptoms from the approximate 23,000 guests and hundreds of staff and volunteers who have visited over the last five days.”