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...