(CBS) — Officials in two north suburban school districts are warning students, staff and parents about possible cases of the mumps, even though they cannot confirm it.

The window of opportunity for confirming a case of the mumps is narrow and both patients are past that point. In fact, the student at Fremont Middle School in Mundelein is back in class.

The other case is at Evanston Township High School. Evanston city Health Director Evonda Thomas-Smith says getting the word out alerts students, parents and staff to watch for symptoms.

“Really significantly inflamed salivary glands coupled with a fever, malaise, fatigue or joint-like achiness,” said Thomas-Smith.

Cases of the once-common childhood disease are now rare. But Thomas-Smith says they show the need to keep vaccinating against it.

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