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...