wear a gas mask ASAP. its the Apocalypse you know. 2 dust masks and a filter mask or 2 also work.
So what i found helped me sleep is the noise cancelling earmuffs. I put them on, bundle up and i can sleep through the entire night. Aside from that, vitamins, cough medicine and water/food to keep you satiated.
I just used a shot and it gave me a cold 
Oh well.
Seems like there are still people underestimating the Flu. “http://en.wikipedia.org/wiki/1918_flu_pandemic”. Good read. It’s not an illness to take too easy.
No one is questioning how serious the flu can be in real life, just whether or not the in-game mechanic of it should work how it currently does.