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...