CHAMPAIGN, Ill. (AP) — An outbreak of mumps at the University of Illinois continues to grow with what officials now say are almost 100 cases.

Champaign-Urbana Public Health District Administrator Julie Pryde told The News-Gazette on Tuesday that 98 cases were confirmed. But she says more are likely with a number of lab tests taken from sick students awaiting confirmation.

Fall classes started this week at the Urbana-Champaign campus.

University health officials are offering free vaccination clinics for students this week.

Mumps is a highly contagious viral illness characterized by swollen jaws and puffy cheeks.

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