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...