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...