School officials believe the norovirus - the same virus blamed for recent mass outbreaks of gastrointestinal illness on cruise ships - is responsible. An outbreak began a week ago and is continuing at Princeton University, which is about six miles away.
"We are coordinating treatment information with that university," Rider said in a statement posted on its main website www.rider.edu. "We have also informed neighboring institutions."
The College of New Jersey also is nearby.
Norovirus symptoms include diarrhea, vomiting, nausea, and stomach cramping, according to the Centers for Disease Control. Symptoms may also cause fever, chills, headache, muscle aches, and fatigue.
Norovirus is not usually serious, and most students should recover within a day or two. It is spread through touching surfaces contaminated with the norovirus, then ingesting foods or liquids.
Rider says it is working with Aramark, its food service, and UNICCO, its custodial service, to sanitize residence hall bathrooms and other areas.
Classes and events are continuing today as scheduled.
University officials say that students feeling ill on campus should call Public Safety at ext. 5029 or 609-896-5029, and that students or employees who are sick should stay home.
The officials are warning students to wash their hands frequently or to use a hand sanitizer.