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...