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...