DENVER (CBS4) – An outbreak of the norovirus is causing concern at a Denver elementary school.

CBS4 News has learned leaders at Oakland Elementary School sent 32 students home Thursday who displayed symptoms.

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“It’s very concerning,” said Alberto Borunda, the guardian of an Oakland Elementary School student. “It’s a lot of kids to be sending home.”

Christine Wilson says her son is one of the students who’s been sick.

“He’s had it three times within the last two months,” said Wilson. “It’s been just going back and forth, he just keeps catching it over and over.”

Denver Health officials confirmed three students and one employee have norovirus. They also told the school to shut down the self-serve salad bar until further inspection.

Oakland Elementary School (credit: CBS)

Oakland Elementary School (credit: CBS)

Denver Public Schools Director of Media Relations Will Jones said Denver public health officials will be back out to inspect the facility again on Monday.

“Denver Environmental Health has instructed us to do a thorough scrub down of the entire school,” Jones said. “We’re doing everything we can to make sure the entire school is safe, that the entire school is clean, and we’re taking the precautions to make sure any child who has not been infected doesn’t get infected.”

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Letters are going home with students who are not sick Thursday to explain the situation.

[graphiq id=”3YSGPCFoEjr” title=”Norovirus Overview” width=”600″ height=”623″ url=”” link=”” link_text=”HealthGrove | Graphiq” ]

The Centers for Disease Control and Prevention describes norovirus as a very contagious disease that leaves patients with stomach pain and nausea.

You can get it from an infected person or by touching contaminated surfaces.

[graphiq id=”7ktEbkUCOfH” title=”Total Outbreaks of Norovirus by Month in the United States” width=”600″ height=”550″ url=”” link=”” link_text=”HealthGrove | Graphiq” ]

Health officials advise any students with symptoms to wait 48 hours before returning back to school.

“The first step is prevention,” Borunda said.

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A CBS4 viewer first tipped CBS4 off to the outbreak of the illness.