First off, I would stay on your gear as planned. Keep your dosing exactly the same. @nd, I'm going to guess that you are in a bulking phase, based off the gear you're using. Continue to eat as much as you can. Don't worry so much about the quality of the foods. Just try to keep cals going in. I usually crave more fats when I get sick and let myself eat more of them than normal, including fast food. Get your shakes in too, to keep your protein intake up. Basically, do the best you can with your diet and get back on track, as soon as you can. 

As for other supps, I would up your mulit to 2x a day and mega dose vit C at around 1000mg 2-3x day. Plus drink plenty of water. 

After I feel a little bit better, I get back in the gym as soon as I can. In fact, it takes a lot to keep me out in the first place. I haven't missed a scheduled training day, in I cant remember how long. I dont miss training unless I have a fever.