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...