"My friends had been sick for a while and weren't getting better .. They were bed-bound, they couldn't move without feeling like they were going to fall to the ground," said CSU, Chico student Karla Camacho.
We all know the dreaded symptoms - a fever, cough, sore throat, aches, fatigue, maybe a runny nose.
"I just got super sick, super fast, almost overnight. I was really hoping it'd go away by the first day of class and thankfully it did!" said student Julia Sloan.
On the first day of the Spring semester, Chico State students are bracing themselves for the return to the close-quarters of the college campus.
"We were really scared, because I'm in a sorority and we were super scared that we were going to get sick and it was going to be this whole chaos," said Camacho.
Since December, Enloe Medical Center in Chico has had 662 flu patients come in. 109 of them were actually admitted.
"It's really petrifying how fast virus and bacteria can evolve to become even stronger than we are, so it's really petrifying to me," said Camacho.
Too many students say they had to make the difficult decision between putting their classmates at risk or missing important material.
"Times get busy, you miss school, and grades start going down," said student Fabian Avalos. "I got sick for a half week, I missed class and sort of just spread it across."
But health care pros all agree: If you have the symptoms, stay home!
"You hear about one students coming to school sick and the whole class gets sick, and the teacher gets sick," Karen Kimmelschue, sorority chapter advisor at CSU, Chico.
While there's no real way to see it coming,some say they build a defense with vitamins, hand-washing, even wearing a mask.
"I never get sick - I just try to go the the gym, keep my immune system up, all the things the doctor recommends," said Carlos Nunez.
Plus, Nunez says he always gets a flu shot, which this year had a 33% success rate in Butte County.
"I myself went and got the flu shot as soon as the season came around and I've been pushing my friends to make sure they did as well," said Avalos.