THERE WAS  A CROWDSOURCED  VACCINE,  
  THAT  COULD BE CREATED REGIONALLY BY  
   MOST   PHARMACEUTICAL   COMPANIES    
  WITHOUT  MUCH  EFFORT,  AND  IT  WAS  
   ESTIMATED   THAT  IT   HAD  SAVED    
       TENS      OF     MILLIONS.       
                                        
 BUT IT  WAS NOT OFFICIALLY RECOGNIZED BY 
 THE WORLD HEALTH  ORGANIZATION,  AND  AS 
 SUCH DID NOT  GIVE  WHAT  THE SANCTIONED 
 (AND   UNOBTAINABLE)   ONES   DID:   THE 
 SUBSKIN  CHIP  THAT WOULD LET YOU  ENTER 
      (OR     LEAVE)      CITIES.       
                                        
  AND THAT'S WHY, EVENTUALLY, WE WOULD  
   CREATE  OUR OWN CHIPS.  THEY  WERE   
  LARGER THAN THE OFFICIAL ONES, AND A  
   LITTLE   UNSTABLE,   AND   NEEDED    
   MAINTENANCE.  BUT  THEY   WORKED!    
  OR, THEY WOULD WORK TOGETHER WITH A   
   LITTLE SOMETHING TO MAKE THE  GUARD  
     LOOK     THE    OTHER     WAY.     
                                      
                                      
                                          
   BUT THE SCANNER SHOWED GREEN, SO...