Nearly 100 students sick after attending their high school prom

Nearly 100 Chicago area high school students became sick with a stomach virus after attending their prom.

Victor J. Andrew High School seniors attended the rite of passage at the Shedd Aquarium in downtown Chicago when more than 90 of the attendees became sick with flu-like symptoms, such as vomiting and diarrhea.

The school was closed Monday while administrators investigated the outbreak. High school student Kacie Johnston was too sick to leave her house on Monday.

"I was vomiting, I had diarrhea, I had a fever, I had everything," she told ABC-owned station WLS-TV in Chicago.

About 500 students attended the suburban high school's prom at the indoor aquarium.

The Shedd Aquarium has been working with the food vendor, Sodexo to identify the source, according to its statement to ABC News.

"The care and well-being of all our guests is a top priority for Shedd Aquarium and something that is taken very seriously," the Shedd Aquarium said in a statement.

"The safety, health, and well-being of our clients and customers is our top priority. We are aware of the alleged food-related illness at the Shedd Aquarium, which has affected students from Victor J. Andrew High School," a Sodexo spokesperson told WLS-TV. "We are conducting a thorough internal investigation in close partnership with the Shedd team and the local health officials. We are committed to food safety and have enjoyed a longstanding and strong performance of food safety procedures and operations at Shedd Aquarium."

One parent claims she wasn't the only one seeking medical attention for her child from an urgent care facility shortly after the Friday night event.

"I was messaging with a few parents last night from immediate care," Edith Paez, whose daughter Elizabeth was among those ill, told WLS-TV.

"Some of them were in the hospital. Some of them were at the actual immediate care where we were," she added.

The city and county health departments are investigating, and the Illinois Department of Public Health said they are aware of the situation.

Bob Nolting, the school's principal, assured parents in a message, which was obtained by WSL-TV, that the school and the district were getting to the root of the cause.

"I have spoken with Shedd Aquarium administration and the Cook County Department of Public Health regarding this information," Nolting wrote. "The Cook County Department of Public Health is conducting an investigation to identify the source of this illness."

The school was cleaned, according to Nolting, overnight to assure no virus seeps its way into the school.