They don't, but even if they did, what difference would it make? 
I'm trying to picture someone lying in bed, dying of a disease because they didn't get the vaccine, saying:
"At least *cough* I don't have *cough* 
autism! *cough* .... 
Blehhhhhhhhh (X_X)"
						
					
					
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	"My only regret is that I have....boneitus" I don't know why but that last bit reminded me of that
 
										 
					 
		    