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...