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...