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...