All classes and extra curricular activities have been cancelled at Mount Allison University in Sackville, N.B. amid fears that a Norwalk-type virus is sickening students.

At least 100 students have come down with symptoms since Thursday, and after discussions with public health officials the university took action.

"They've advised us to try and avoid contact which is why we decided to close all our public buildings and cancel classes for this afternoon, as well as all extra curricular activities for this weekend. We're trying to contain the virus," Laura Dillman, the university's media communications coordinator, told CTV Newsnet.

Academic buildings, the cafeteria, residences and the library will remain open, but members of the public have been asked to stay away.

Students have been told to take precautions to minimize the risk, such as frequent hand washing and avoiding unnecessary contact.

Dillman said officials are awaiting test results.

"Right now preliminary testing from the department of health shows it to be a Norwalk-type virus, but we can't confirm that. It takes a few days for these types of test to go through."

Stephen McClatchie, vice-president of academics and research, indicated students started getting sick on Thursday.

Some students sought treatment at Sackville Memorial Hospital, while others remained in their rooms.

Public health officials were called in to investigate as soon as the university became aware of the situation.

"We are continuing to care for students, providing as much information as we can to them and to their parents -- about how to prevent further spread of the stomach flu-like symptoms," he wrote in the letter to the public.

The illness generally lasts 24 to 48 hours, but typically has no serious lasting effects. It often strikes in places where people live in close contact with each other.

A news conference is scheduled for Friday afternoon.

Symptoms of Norwalk include acute diarrhea, abdominal cramps, nausea and vomiting, as well as headaches and fever.

The most effective steps to take to avoid developing the gastrointestinal virus are as follows:

• Wash hands with soap and warm water after toilet visits and before preparing or eating food;
• Cook all shellfish thoroughly before eating;
• Wash raw vegetables before eating;
• Dispose of sewage in a sanitary manner;
• Food handlers with symptoms of Norwalk-like illness should not prepare or touch food.