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...