Meghan Beretta, a sophomore from Passaic County, N.J., said someone in her history class came down with the virus, but it was shortly before spring break, so she didn't expect to have a high risk of exposure.
"I've been pretty healthy," Beretta said.
There is some worry among students trying to avoid a bout of illness — "It's been the subject of jokes when anybody has a cold or anything," said John Kelley, a sophomore from Fairfax, Va.
"But it doesn't pose a lot of concerns for me in my day-to-day life," Kelley said.
Cause: Viral infection
Symptoms: Swelling and tenderness of salivary and other glands, testicles, ovaries; low-grade fever; headache; loss of appetite
Incubation period: 16-18 days
Transmission: Spread via coughing, other contact with saliva or other mouth, nose and throat fluids
Prevention: MMR vaccine series considered 90 percent effective; isolation used to prevent spread of virus