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...