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...