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...