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...