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...