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Phylacogens. 
Am.  Jour.  Plmrm. 
July,  1913. 
organisms  which  are  always  present  in  great  variety  and  number. 
As  an  illustration,  attention  may  be  directed  to  the  now  com- 
monly accepted  idea  that  in  pulmonary  tuberculosis  the  greatest 
danger  to  the  patient,  much  of  the  difficulty  of  the  treatment,  and 
many  of  the  most  notable  symptoms,  such  as  loss  of  weight,  high 
temperature,  disturbance  of  circulation,  purulent  expectoration, 
destruction  of  tissue,  etc.,  are  due  to  the  complicating  organisms, 
and  if  the  so-called  "  mixed  infection  "  can  be  checked  or  elimi- 
nated, efforts  may  be  directed  against  the  bacillus  tuberculosis  with 
far  greater  success  than  has  heretofore  been  possible  in  the  treat- 
ment of  this  condition. 
Dr.  Schafer  points  to  the  fact  that  the  administration  of  bac- 
terial vaccines  to  patients  suffering  from  infection  not  infrequently 
fails  of  effect  because  the  truth  of  the  above  assumption  is  not  recog- 
nized, especially  when  the  treatment  consists  in  the  use  of  a  vac- 
cine made  from  a  single  species  of  organism  isolated  from  the 
patient.  Bacterial  vaccines  made  from  a  single  species  of  organism 
proved  successful  in  many  cases,  but  the  multiplicity  of  "  com- 
bined "  bacterial  vaccines  now  in  use  points  to  the  rapidly  develop- 
ing conclusion  that  the  great  majority  of  patients  require  something 
more  than  treatment  with  a  vaccine  made  from  one  organism;  the 
success  attending  the  use  of  polyvalent  bacterial  vaccines  made 
from  a  number  of  different  species,  even  when  used  in  pathologic 
conditions  apparently  due  to  one  species,  points  to  the  likelihood 
of  this  theory  being  correct. 
Name. 
The  term  "  Phylacogen  "  has  been  coined  to  distinguish  the 
several  new  bacterial  derivatives  (devised  by  Dr.  A.  F.  Schafer  and 
produced  by  Parke  Davis  &  Co.)  from  other  remedial  agents  of 
similar  character  that  may  be  offered  to  the  medical  profession. 
Each  specific  Phylacogen  is  further  identified  by  the  prefixion  of  the 
name  of  the  pathological  condition  in  which  it  is  indicated — as 
Gonorrhea  Phylacogen,  Rheumatism  Phylacogen,  Pneumonia 
Phylacogen,  etc. 
The  term  "Phylacogen"  (derived  from  two  Greek  words, 
phulax  (pbXaZ  a  guard,  and  gennan  tevvolv  to  produce)  means 
"  Phylaxin  producer.'*  Phylaxin  is  the  name  applied  by  Hankin  to 
a  defensive  proteid  found  in  animals  that  have  acquired  an  artificial 
