PARASITES  OF  INFECTIOUS  DISEASES. 
143 
PARASITES  OF  INFECTIOUS  DISEASES. 
Prof.  Hallier,  of  Jena,  read  a  paper  on  this  subject  before  the 
Annual  Congress  of  German  Naturalists  and  Physicians,  which 
met  in  Dresden,  in  September  last.  He  said  that  it  was  Bohm, 
who,  thirty  years  ago,  first  discovered  minute  organized  beings 
in  the  intestines  of  cholera  patients.  This  important  observa- 
tion, however,  remained  unnoticed  for  a  considerable  time.  The 
minute  organisms  observed  by  Bohm  belonged  to  the  species  of 
Bacteria  and  Vibrio,  which  had  been  known  as  far  back  as  the 
last  century,  but  had  only  been  accurately  examined  by  Ehren- 
berg,  and  which  were  by  some  zoologists  classed  amongst  the 
Infusoria,  while  others  placed  them  with  the  Algae  and  Fungi. 
Quite  recently  a  number  of  observers  had  commenced  to  investi- 
gate their  origin  and  their  conditions  of  life,  because  the  fact  of 
their  being  found  in  fermenting  and  putrid  substances,  as  well 
as  in  pathological  liquids,  had  invested  them  with  a  considerable 
degree  of  interest.  It  had  been  too  much  the  custom  in  former 
times,  as  soon  as  any  such  formations  were  observed,  to  make 
immediately  a  number  of  species  and  genera  of  them,  without 
investigating  at  all  the  origin  of  these  minute  organisms.  It 
had  now  been  shown  that  they  were  nothing  but  lower  grades  of 
development  of  higher  classes  of  fungi.  In  sixteen  infectious 
diseases  the  presence  of  a  peculiar  and  characteristic  fungus  had 
now  been  demonstrated — viz.,  in  cholera,  typhoid  fever,  typhus, 
measles,  dysentery,  and  certain  diseases  of  the  domesticated 
animals.  Whether  the  parasite  was  the  actual  cause  of  the 
pathological  process  could  at  present  not  be  made  out  with  any 
degree  of  certainty  ;  but  the  fact  that  certain  peculiar  forms  of 
parasites  were  invariably  present  in  certain  diseases  was  no 
doubt  most  significant.  In  the  disease  of  the  silkworm  it  had 
been  irrefutably  proved  that,  in  spite  of  numerous  conditions 
favoring  the  tendency  to  the  development  of  the  disease,  the 
parasite  itself  was  the  sole  and  exclusive  cause  of  it,  and  that 
not  only  the  hereditary  transmission,  but  also  the  epidemic  char- 
acter of  the  complaint,  was  entirely  dependent  upon  the  presence 
of  the  parasite. —  The  Med.  News  and  Library,  Jan.  1869, /rom 
Med.  Times  and  Qaz.,  Oct.  31,  1868. 
