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...