﻿ENTOMOLOGICAL 
  ASPECTS 
  OF 
  AN 
  OUTBREAK 
  OF 
  SLEEPING 
  SICKNESS. 
  347 
  

  

  both 
  as 
  carriers 
  and 
  to 
  avoid 
  carrying, 
  and 
  were 
  also 
  probably 
  exhausted 
  by 
  excessive 
  

   porterage. 
  So, 
  possibly, 
  were 
  some 
  of 
  their 
  fellow- 
  porters 
  who 
  may 
  have 
  been 
  

   carriers 
  of 
  trypanosomes. 
  In 
  1918, 
  and 
  probably 
  already 
  in 
  1917, 
  the 
  Neumann 
  

   operations 
  having 
  reduced 
  food 
  supplies 
  and 
  prevented 
  hoeing, 
  the 
  people 
  were 
  

   scattered 
  by 
  a 
  famine 
  for 
  the 
  second 
  time 
  over 
  the 
  face 
  of 
  the 
  country 
  seeking 
  food, 
  

   and 
  came 
  into 
  fuller 
  contact 
  than 
  ever 
  with 
  surrounding 
  peoples. 
  Influenza 
  also 
  

   swept 
  through 
  the 
  area, 
  and 
  smallpox 
  through 
  a 
  portion 
  of 
  it. 
  Additional 
  game 
  

   extermination 
  took 
  place 
  in 
  the 
  neighbourhood 
  of 
  the 
  larger 
  populations 
  in 
  which 
  

   the 
  game 
  was 
  greatly 
  reduced 
  already. 
  

  

  It 
  is 
  stated 
  by 
  natives 
  that 
  cases 
  with 
  the 
  sleeping 
  sickness 
  symptoms 
  were 
  first 
  

   noted 
  at 
  the 
  end 
  of 
  the 
  famine 
  (when, 
  to 
  judge 
  from 
  the 
  date 
  of 
  Capt. 
  Currie's 
  

   observation, 
  they 
  were 
  probably 
  already 
  numerous), 
  and 
  it 
  is 
  probable 
  (a) 
  that 
  a 
  try- 
  

   panosome 
  or 
  strain 
  of 
  trypanosome 
  actually 
  or 
  potentially 
  pathogenic 
  to 
  man 
  had 
  

   been 
  introduced 
  from 
  one 
  of 
  the 
  various 
  sources 
  I 
  have 
  indicated 
  above 
  or 
  was 
  already 
  

   present 
  in 
  the 
  area 
  ; 
  (b) 
  that 
  first 
  their 
  other 
  hardships 
  and 
  then 
  the 
  famine 
  had 
  

   weakened 
  the 
  people's 
  power 
  of 
  destroying 
  the 
  injected 
  trypanosomes 
  (the 
  great 
  

   Busoga 
  epidemic 
  similarly 
  accompanied 
  a 
  severe 
  famine) 
  ; 
  (c) 
  that 
  out 
  of 
  several 
  

   localities 
  in 
  which 
  this 
  trypanosome 
  was 
  present 
  and 
  might 
  have 
  caused 
  trouble 
  

   had 
  it 
  not 
  been 
  for 
  the 
  fly-diverting, 
  virulence-controlling 
  presence 
  of 
  game, 
  it 
  did 
  

   actually 
  first 
  spread 
  and 
  establish 
  its 
  full 
  virulence 
  in 
  one 
  of 
  them 
  — 
  eventually 
  for 
  

   relatively 
  undebilitated 
  man. 
  In 
  that 
  locality, 
  between 
  Usmao 
  and 
  Ngasamo, 
  game 
  

   having 
  been 
  greatly 
  reduced, 
  the 
  fly 
  was 
  devoting 
  that 
  special 
  attention 
  to 
  human 
  

   beings 
  that 
  we 
  ourselves 
  noted 
  in 
  this 
  more 
  gameless 
  area, 
  and 
  that 
  it 
  always 
  does 
  

   devote 
  to 
  human 
  beings 
  when 
  deprived 
  of 
  other 
  food. 
  

  

  Famine 
  and 
  game 
  destruction 
  appear 
  to 
  be 
  the 
  most 
  dangerous 
  combination. 
  

   They 
  tend 
  to 
  occur 
  together, 
  for 
  game 
  destruction 
  by 
  natives 
  takes 
  place 
  rather 
  

   specially 
  during 
  famine, 
  but 
  the 
  destruction 
  in 
  the 
  Simiyu 
  area 
  was 
  probably 
  

   exceptional. 
  Game 
  destruction 
  was 
  taking 
  place 
  in 
  that 
  locality 
  especially 
  for 
  years 
  

   before 
  the 
  war 
  ; 
  it 
  was 
  doubtless 
  accentuated 
  by 
  the 
  relaxation 
  of 
  attempts 
  at 
  game 
  

   preservation 
  during 
  the 
  war 
  ; 
  it 
  would 
  have 
  been 
  reinforced 
  by 
  the 
  killing 
  indulged 
  

   in 
  by 
  that 
  portion 
  of 
  the 
  Belgian 
  expedition 
  which 
  passed 
  through 
  this 
  country 
  ; 
  

   wherever 
  I 
  have 
  travelled 
  in 
  the 
  west 
  of 
  the 
  territory, 
  the 
  destruction 
  of 
  game 
  by 
  

   the 
  Belgian 
  forces 
  has 
  been 
  described 
  to 
  me 
  by 
  the 
  natives 
  as 
  something 
  quite 
  excep- 
  

   tional 
  ; 
  and 
  it 
  wouldhave 
  reachedits 
  climax 
  finally, 
  in 
  relation 
  to 
  any 
  game 
  that 
  remained, 
  

   during 
  the 
  famine 
  as 
  the 
  result 
  of 
  hunger 
  and 
  movement. 
  And 
  all 
  this 
  destruction, 
  

   while 
  it 
  was 
  not 
  entirely 
  confined 
  to 
  the 
  area 
  between 
  Usmao 
  and 
  the 
  Duma, 
  was 
  

   exceptionally 
  effective 
  there 
  because 
  this 
  region 
  bordered 
  on 
  the 
  areas 
  of 
  heaviest 
  

   population, 
  and 
  was 
  with 
  difficulty 
  reached 
  and 
  replenished 
  by 
  the 
  annual 
  game 
  

   movements. 
  I 
  have 
  shown 
  that 
  the 
  position 
  was 
  very 
  nearly 
  indeed 
  that 
  which 
  

   would 
  have 
  been 
  brought 
  about 
  had 
  anyone 
  enclosed 
  a 
  piece 
  of 
  country 
  with 
  a 
  

   nearly 
  game-proof 
  fence 
  and 
  killed 
  most 
  of 
  the 
  game 
  inside 
  it, 
  while 
  leaving 
  the 
  

   human 
  population 
  exposed 
  to 
  the 
  attacks 
  of 
  the 
  tsetse. 
  The 
  game, 
  it 
  seems 
  certain, 
  

   had 
  already 
  increased 
  between 
  the 
  famine 
  and 
  my 
  visit, 
  particularly 
  on 
  the 
  Duma, 
  

   yet, 
  even 
  so, 
  it 
  was 
  very 
  scarce 
  as 
  compared 
  with 
  the 
  game 
  about 
  Nasa 
  and 
  

   beyond 
  Ngasamo, 
  and 
  this 
  difference 
  was 
  still 
  being 
  strongly 
  reflected 
  in 
  the 
  habits 
  

   of 
  the 
  tsetses. 
  

  

  Whether 
  T. 
  brucei 
  of 
  the 
  game 
  then 
  became 
  converted 
  into 
  T. 
  rhodesiense 
  of 
  man, 
  

   or 
  a 
  human 
  trypanosome 
  that 
  was 
  present 
  in 
  the 
  game 
  or 
  in 
  some 
  human 
  carrier 
  

   who 
  lived 
  in 
  or 
  visited 
  the 
  area 
  secured 
  vectors 
  and 
  an 
  enhanced 
  virulence, 
  it 
  was 
  

   clear 
  later 
  that, 
  once 
  the 
  initial 
  catastrophe 
  has 
  occurred, 
  man 
  becomes 
  very 
  definitely 
  

   the 
  reservoir 
  and 
  the 
  vertebrate 
  disseminator. 
  On 
  the 
  brucei 
  view 
  (as 
  modified 
  bv 
  

   Taute's 
  results 
  and 
  Duke's 
  suggestions) 
  a 
  human 
  infect, 
  carrying 
  a 
  parasite 
  that 
  is 
  

   already 
  virulent 
  for 
  man, 
  must 
  in 
  any 
  case 
  be 
  far 
  more 
  dangerous 
  than 
  a 
  game 
  

   animal, 
  for 
  the 
  parasites 
  in 
  the 
  blood 
  of 
  the 
  latter 
  would 
  seem 
  likely 
  to 
  require 
  some 
  

   passages 
  through 
  man, 
  probably 
  by 
  means 
  of 
  direct 
  transmission 
  and 
  perhaps 
  at 
  

  

  