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...