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...