Although statistically, you are safer running a marathon than driving a car, you should always listen to your body when running. There is a difference in running through fatigue or pain and continuing to run when you are doing physical harm to yourself. It's a fine line and it may be de difficult to tell the difference. This being said, we runners are stubborn:
"We can run through it."
"We've done it in the past."
"We didn't train for 3 months to give up at mile 18."
These may be the thoughts we want to think... but we need to know that there is always another race to finish and another day to run. Every runner should get an annual physical from your doctor or a routine check up to help prevent forseeable tragedy. But understand this: DOING THIS DOES NOT MEAN THIS CANNOT HAPPEN TO YOU. This can happen to any runner. The three runners that died in Detroit yesterday were described as "healthy" and were avid runners.
I've seen numbers that say deaths occur 0.8 per 100,000 in marathons... Those are pretty good numbers, all things considered, but that also (again) states you are not 100% risk free.
Runner's deaths during races always seem to be reported (and rightfully so), but let's not forget the accomplishments that are reached out there. In a given race, you are looking at 5,000 plus runners and larger races such as New York, up to 37,000. If a quarter of those people are finishing their first marathon and another couple thousand PR, those are amazing feats. Individual achievements cannot be reported or receive National coverage, but accomplishments are reached by thousands of people at every race. First timers, PRs, sub 4 hours, Boston Qualifiers, placing in your age group, marathon number 10, alphabet marathon series, 50 state marathon club, etc.
When you take a moment of silence to acknowledge the loss of a fellow runner, remember that runners support each other and although we all feel the loss of an individual, we must celebrate and encourage each others feats and continue to strive for greatness for ourselves and those that can no longer run with us.