School officials said it is most likely norovirus, the so-called "cruise ship virus."
Students began getting sick January 23rd, with nausea and vomiting. They are getting better in 24 to 48 hours, as is the usual course with norovirus.Most of the 100 or so students recovered on their own. However, several went to local emergency departments because they were dehydrated. They received intravenous fluids, and they were released.
The university's medical staff has consulted with the Pennsylvania Health Department, as well as Radnor, Delaware County officials, and the Montgomery County health department. They don't believe it was a foodborne illness, since those affected ate in different places. They do believe the source was viral.
There have been scattered outbreaks of the virus this winter.
Two weeks ago, Lehigh Valley Hospital's Chew street hospital closed down one unit after nearly 50 patients and staff members came down with the bug. In addition, an unknown number of local schools have had cases.
The virus spread quickly, transmitted by hand and on surfaces. The best defense, according to the CDC, is to wash your hands often, and sanitize objects such as telephones, desks, tables, computer keyboards, etc. which are used by a large number of people.
If you get sick, get lots of fluids. You are still contagious up to 72 hours after you start feeling better.