COVID-19 and the Missing Bullet Holes

The story is told about how the US Army figured out the best way to armor its airplanes in WWII. Because armor slows planes down, it could not simply be layered on indiscriminately. So engineers had to figure out which parts of the plane needed it most. To find out, they inspected planes returning from battle. Because the planes were presumably being hit by anti-aircraft fire randomly, the parts of the planes that had no bullet holes must have been parts that could not afford to be hit, as planes being hit there were not returning. Those parts (the engines) got the armor.

I heard this story from my college room mate more than fifty years ago, but its logic, like the curious incident of the dog in the night time, stuck with me as a way to approach certain types of problem.  One such problem may be finding an "accidental" cure for COVID-19.

Recent reports suggest that chloroquine and hydroxychloroquine, anti-malarials long available generically in the US and used now for autoimmune diseases like rheumatoid arthritis and lupus, may prevent/cure COVID-19. The possibility of prevention (or cure so quickly as to amount to prevention) brings to mind the airplanes and their bullet holes. Everyone who seeks medical care for anything is asked for a list of medications they take. What if, despite the fact that something like .25% of the population takes CQ or HCQ  - I'm guessing; the number doesn't really matter so long as it's big enough - almost no one presenting with COVID-19 takes either of those drugs? Wouldn't that raise an inference that the drug is providing protection? And, of course, this bit of induction is not limited to these drugs. A bit of data-mining should reveal any significantly under-represented medication in the COVID-19 population.

Yes, clinical testing needs to be done, but, as Henry David Thoreau wrote, some circumstantial evidence is quite powerful, as when you find a trout in the milk. If people taking HCQ in France are getting better, and people already on CQ or HCQ here (and anywhere else) are not getting sick, We may have a way out of this mess before a real vaccine can be developed, tested, and distributed.

This thought must have crossed the minds of people in a position to look into it. So, if a popular medicine that incidentally prevents COVID-19 infection or symptoms is out there, it will be detected, and we will be back to our lives sooner than most people believe.