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...