I'm not a doctor or anything, but I think that if you're ill, you do need to take it easy for a few days. Part of losing weight is learning to do it over the long haul, and that means being able to make it fit with your life--including bouts with colds or flu.
Or you could compromise: step back your exercise to some lighter level for a few days. If you jog, walk. If you have a stationary bike, don't raise the resistance on it. Take a vacation from Jillian in favor of some light yoga or free-form dancing. Skip the heavy lifting. You'll still stay active, but still get a little bit of a respite from heavy-duty effort.
Look for Eliana's chronicle of her exercise break elsewhere on the forums; she's been tremendously successful and recorded what she did step by step. It'll give you some valuable insight into exercise, taking breaks, and varying routines.
Congratulations on ridding yourself of that annoying pound! May all of its brothers and sisters soon follow it.