By RACHAEL MCDONALD • OCT 30, 2015

Lane County Health officials say Norovirus is the most likely cause of more than one hundred teachers and students becoming ill Thursday at O'Hara Catholic School in Eugene. The school is closed Friday and likely to re-open next week.

Lane County Health Department spokesman Jason Davis says while Norovirus is easily transmitted, it's generally confined to a particular place. That's why it's often called the "cruise ship" virus.  Davis says washing your hands is one of the best ways to prevent it. But you have to do it right.

Davis: "What you need to do is you need to get your hands completely lathered with soap and spend a good 20-30 seconds really scrubbing them, underneath the fingernails, in between your fingers, on top and your palms and make sure you really scrub those hands. That's what's going to kill most of the germs."

Davis says the school was scrubbed down Thursday with a chlorine-bleach mix. Norovirus can cause vomiting, diarrhea and stomach cramps.