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...