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...