Sickness during my taper

The original plan after completing my 20 mile training run left me 3 weeks to taper.

Which meant the following schedule.

Week 1
M - rest
T - rest
W - 3 miles
R - 4 miles
F - 3 miles
S - 8 - 10 miles
S - rest

Week 2
M - 3 miles
T - 4 miles
W - 3 miles
R - rest
F - 3 miles
S - 8 miles
S - rest

Week 3 - Marathon week
M - 3 miles
T - 2 miles
W - rest
R - rest
F - 2 miles
S - 2 miles
S - Marathon!

Well, I got sick. I ran the training run sick but that wasn't as bad as what was to come. First, the head cold/chest stuff got super bad, so I figured I'd rest right through to Thursday of that week 1 schedule, and start running again on Friday. I knew full well that those extra couple day off and meant no harm to my training. But Thursday night I started what I found out to be a stomach infection. The rest of Week 1 and until Saturday of week 2 was fighting that infection. It is now Wednesday of Marathon week, and I'll be doing a short run at lunch to work at getting my feet back under me. I'm not letting this setback change my goals, but I will be more aware of my "vitals" throughout Sunday, and if I have to slow down or even take a break I will to get through it. My hope is that I did enough training to get me to that finish line in under four hours, but the realist in my is thinking a fallback of 4:15-4:30 may happen as well.