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...