﻿317 
  

  

  THE 
  ENTOMOLOGICAL 
  ASPECTS 
  OF 
  AN 
  OUTBREAK 
  OF 
  SLEEPING 
  

   SICKNESS 
  NEAR 
  MWANZA, 
  TANGANYIKA 
  TERRITORY.* 
  

  

  By 
  C. 
  F. 
  M. 
  Swynnerton, 
  F.L.S., 
  F.E.S. 
  

   (Plates 
  XII— 
  XVII.) 
  

  

  Contents. 
  

  

  I. 
  Introduction 
  

  

  II. 
  The 
  Country 
  generally 
  

  

  III. 
  The 
  Open 
  Country 
  

  

  IV. 
  The 
  Acacia 
  Thorn 
  Area 
  

   V. 
  The 
  People 
  

  

  VI. 
  The 
  other 
  Hosts 
  of 
  the 
  Fly 
  . 
  . 
  

  

  VII. 
  The 
  Species 
  of 
  Glossina 
  Present 
  

  

  VIII. 
  The 
  Seasonal 
  Distribution 
  and 
  Preferences 
  in 
  Vegetation 
  of 
  the 
  Fly 
  

  

  IX. 
  An 
  Apparent 
  Method 
  of 
  Concentration 
  

  

  X. 
  The 
  Feeding 
  Habits 
  and 
  Sex 
  Proportions 
  of 
  the 
  Fly 
  

  

  XI. 
  Breeding 
  Places 
  of 
  the 
  Fly 
  

  

  XII. 
  The 
  Following-distance 
  of 
  Female 
  Flies 
  

  

  XIII. 
  Distance 
  of 
  Attack 
  and 
  Protection 
  of 
  Roads 
  

  

  XIV. 
  Miscellaneous 
  Motes 
  (Settling 
  Habits, 
  Relation 
  of 
  Game 
  and 
  Cattle, 
  Banishment 
  

  

  of 
  Tsetse 
  by 
  Partial 
  Clearing, 
  Test 
  of 
  a 
  Tsetsefuge, 
  Protection 
  against 
  Bites) 
  

  

  XV. 
  The 
  Known 
  Infected 
  Area 
  and 
  the 
  Tsetse 
  responsible 
  for 
  the 
  Spread 
  of 
  the 
  

  

  Infection 
  

  

  XVI. 
  Three 
  Types 
  of 
  Sleeping 
  Sickness 
  Villages 
  

  

  XVII. 
  Duration 
  and 
  Course 
  of 
  the 
  Infection 
  

  

  XVIII. 
  The 
  Facilities 
  for 
  Direct 
  Transmission 
  

  

  XIX. 
  The 
  Relation 
  of 
  the 
  Game 
  to 
  the 
  Outbreak 
  

  

  XX. 
  Possibilities 
  of 
  Spread 
  

  

  XXI. 
  Immediate 
  Local 
  Measures 
  

  

  XXII. 
  A 
  Campaign 
  against 
  the 
  Fly 
  

  

  XXIII. 
  General 
  Prophylactic 
  Measures 
  

  

  XXIV. 
  Conclusion 
  

  

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  I. 
  — 
  Introduction. 
  

  

  Information 
  volunteered 
  by 
  Salim, 
  the 
  native 
  headman 
  of 
  Basheshi, 
  near 
  Maswa, 
  

   drew 
  attention 
  to 
  the 
  outbreak 
  of 
  sleeping 
  sickness 
  here 
  described 
  late 
  in 
  February 
  

   1922. 
  

  

  Dr. 
  G. 
  Maclean, 
  the 
  Medical 
  Officer 
  at 
  Mwanza, 
  at 
  once 
  earned 
  out 
  an 
  energetic 
  

   investigation. 
  He 
  found 
  by 
  blood 
  examination 
  that 
  the 
  disease 
  (which 
  had 
  at 
  first 
  

   been 
  regarded 
  by 
  the 
  natives 
  as 
  " 
  safula 
  " 
  or 
  hookworm) 
  was 
  in 
  fact 
  trypanosomiasis. 
  

   He 
  ascertained 
  roughly 
  the 
  extent 
  of 
  country 
  that 
  had 
  been 
  invaded 
  by 
  it 
  already 
  

   in 
  the 
  Simiyu-Duma 
  area 
  and, 
  with 
  the 
  Senior 
  Commissioner, 
  at 
  once 
  took 
  steps 
  

   for 
  the 
  erection 
  of 
  hospitals 
  in 
  fly-free 
  parts 
  of 
  the 
  Sultanates 
  most 
  affected 
  and 
  for 
  

   the 
  segregation 
  there 
  of 
  the 
  sick. 
  

  

  It 
  was 
  obviously 
  an 
  exceptional 
  opportunity 
  to 
  gain 
  some 
  idea 
  at 
  first 
  hand 
  of 
  the 
  

   combination 
  of 
  factors 
  necessary 
  to 
  bring 
  about 
  an 
  outbreak 
  of 
  human 
  trypanoso- 
  

   miasis 
  in 
  epidemic 
  form 
  before 
  these 
  should 
  have 
  been 
  masked 
  by 
  remedial 
  measures 
  

   — 
  particularly 
  so 
  if 
  it 
  should 
  be 
  of 
  Nyasaland 
  tj'pe, 
  and 
  in 
  the 
  event, 
  furthermore, 
  

   of 
  T. 
  rhodesiensc 
  and 
  T. 
  brucei 
  being 
  finally 
  shown 
  to 
  be 
  conspecific. 
  

  

  * 
  This 
  is 
  a 
  revision 
  of 
  a 
  report 
  sent 
  to 
  the 
  Tanganyika 
  Territory 
  Government 
  from 
  Mombasa 
  

   on 
  3rd 
  July. 
  The 
  report 
  (in 
  order 
  to 
  be 
  in 
  time 
  to 
  assist 
  decisions 
  as 
  to 
  measures) 
  was 
  written 
  

   in 
  great 
  haste, 
  under 
  difficulties 
  and 
  without 
  much 
  reference 
  to 
  my 
  notes, 
  while 
  travelling 
  to 
  catch 
  

   a 
  steamer, 
  and 
  this 
  paper 
  should 
  be 
  regarded 
  as 
  replacing 
  it. 
  

  

  