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...