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...