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...