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...