Stomach Flu Outbreak

Recently, one of my students wrote me an e-mail to tell me that she had missed class due to the stomach flu. Early in the semester another student did the same thing. This made me uncomfortable. Two students with the stomach flu, and me in the same room with them for 45 minutes, three days a week. But, I got through those two incidents without contracting the virus, and had almost forgotten about it when today, another student of mine came up to me after class and told me that she had the stomach flu and did not even want to think about food. I was trying not to breathe in as she talked. I was very upset and tried to shoo her away as quickly as I could, agreeing to whatever she said. I was trying to scurry quickly away from her without being offensive. I was upset, but somehow I still had my composure. And that is something that I can be proud of. After my 2nd class of the day, a male student came up to me to tell me why he had missed class last week. Same thing. I was so upset by this point that I forgot all niceties and ordered him to step back away from me. And now I'm terrified. Does this constitute an outbreak? I mentioned this story to the administrative assistant in my division office, and she said that three of the teachers in our department had it last week. And then I moved into the panic mindset. I got out of there as soon as I could, and almost hit a pole while driving home. I was going to head straight to my kitchen cabinet which houses the sedatives, but then I decided to wait, and see if I could ride it out. I tried to eat soup broth and toast, things that are easy to eat when one is panicking about getting the stomach flu, and then calmed down a bit and did the dishes. A few hours later I was finally hungry and ate the stew I prepared yesterday. I'm drinking my chamomile tea and reasearching the internet for Stomach Flu 2009. I'm finding articles like this and this. I'm panicing again. I'm about to lie down in bed with a sedative and some Law and Order.