﻿588 
  ANNUAL 
  REPORT 
  SMITHSONIAN 
  INSTITUTION, 
  1943 
  

  

  months 
  after 
  vaccination. 
  Groups 
  vaccinated 
  with 
  certain 
  lots 
  of 
  

   vaccine 
  showed 
  absence 
  of 
  demonstrable 
  protective 
  antibodies 
  in 
  from 
  

   50 
  to 
  80 
  percent 
  of 
  the 
  cases. 
  Investigation 
  showed 
  that 
  the 
  ineffective 
  

   lots 
  of 
  vaccine 
  contained 
  living 
  virus 
  which 
  had 
  undergone 
  over 
  309 
  

   passages 
  in 
  tissue 
  culture, 
  while 
  the 
  virus 
  previously 
  used 
  so 
  success- 
  

   fully 
  had 
  been 
  passaged 
  only 
  from 
  229 
  to 
  255 
  times. 
  It 
  was 
  necessary 
  

   to 
  test 
  and 
  revaccinate 
  many 
  persons 
  for 
  their 
  protection. 
  There 
  

   seemed 
  to 
  have 
  been 
  a 
  qualitative 
  change 
  in 
  the 
  virus 
  which 
  resulted 
  

   in 
  a 
  drop 
  in 
  its 
  antigenicity. 
  Whether 
  this 
  was 
  directly 
  due 
  to 
  an 
  

   excessive 
  number 
  of 
  passages 
  is 
  being 
  subjected 
  to 
  experimental 
  test 
  

   in 
  Colombia 
  and 
  the 
  International 
  Health 
  Division 
  Laboratories 
  in 
  

   New 
  York, 
  as 
  well 
  as 
  in 
  Brazil. 
  The 
  return 
  to 
  lower 
  passage 
  material 
  

   has 
  again 
  brought 
  satisfactory 
  results. 
  To 
  prevent 
  the 
  recurrence 
  

   of 
  this 
  episode, 
  new 
  lots 
  of 
  vaccine 
  in 
  Brazil 
  are 
  being 
  used 
  first 
  in 
  

   vaccinating 
  small 
  groups 
  of 
  persons 
  whose 
  serum 
  must 
  pass 
  a 
  rigid 
  

   test 
  for 
  protective 
  antibodies 
  before 
  the 
  lot 
  is 
  sent 
  into 
  the 
  field 
  for 
  use. 
  

   In 
  simplest 
  terms, 
  the 
  outstanding 
  features 
  of 
  the 
  yellow 
  fever 
  

   situation 
  in 
  the 
  Americas 
  are: 
  (1) 
  absence 
  of 
  definite 
  outbreaks 
  of 
  

   urban, 
  aegyp 
  ^'-transmitted 
  yellow 
  fever 
  anywhere; 
  (2) 
  absence 
  of 
  

   recognized 
  yellow 
  fever 
  of 
  any 
  transmission 
  type 
  outside 
  of 
  South 
  

   America; 
  (3) 
  jungle-transmitted 
  yellow 
  fever, 
  endemic 
  and 
  as 
  migrat- 
  

   ing 
  epidemics, 
  in 
  wide 
  areas 
  of 
  the 
  interior 
  of 
  South 
  America; 
  

   (4) 
  effective 
  methods 
  for 
  keeping 
  cities 
  noninfectible 
  through 
  aegypti 
  

   control; 
  and 
  (5) 
  a 
  safe 
  and 
  effective 
  way 
  to 
  immunize 
  against 
  yellow 
  

   fever 
  and 
  prevent 
  its 
  spread 
  from 
  the 
  jungle 
  to 
  infectible 
  cities. 
  

  

  LITERATURE 
  CITED 
  

  

  Findlay, 
  G. 
  M., 
  and 
  MacCaixum, 
  F. 
  O. 
  

  

  1937. 
  Note 
  on 
  acute 
  hepatitis 
  and 
  yellow 
  fever 
  immunization. 
  Trans. 
  Roy. 
  

   Soc. 
  Trop. 
  Med. 
  and 
  Hyg., 
  vol. 
  31, 
  p. 
  297. 
  

   Lloyd, 
  W., 
  Theiler, 
  M., 
  and 
  Ricci, 
  N. 
  I. 
  

  

  1936. 
  Modification 
  of 
  the 
  virulence 
  of 
  yellow 
  fever 
  virus 
  by 
  cultivation 
  in 
  

  

  tissues 
  in 
  vitro. 
  Trans. 
  Roy. 
  Soc. 
  Trop. 
  Med. 
  and 
  Hyg., 
  vol. 
  29, 
  

   p. 
  481. 
  

   Roubaud, 
  B., 
  Stefanopoulo, 
  G. 
  J., 
  and 
  Finblay, 
  G. 
  M. 
  

  

  1937. 
  Essais 
  de 
  transmission 
  par 
  les 
  stegomyies 
  du 
  virus 
  amaril 
  de 
  cultures 
  

  

  en 
  tissu 
  embryonnaire. 
  Bull. 
  Soc. 
  Path. 
  Txot, 
  vol. 
  30, 
  p. 
  581. 
  

   Sawyer, 
  W. 
  A. 
  

  

  1939. 
  Yellow 
  fever. 
  Oxford 
  Medicine, 
  vol. 
  5, 
  p. 
  731. 
  

   Sawyer, 
  W. 
  A., 
  Bauer, 
  J. 
  H., 
  and 
  Whitman, 
  L. 
  

  

  1937. 
  The 
  distribution 
  of 
  yellow 
  fever 
  immunity 
  in 
  North 
  America, 
  Central 
  

   America, 
  the 
  West 
  Indies, 
  Europe, 
  Asia, 
  and 
  Australia, 
  with 
  special 
  

   reference 
  to 
  the 
  specificity 
  of 
  the 
  protection 
  test. 
  Amer. 
  Journ. 
  

   Trop. 
  Med., 
  vol. 
  17, 
  p. 
  137. 
  

   Sawyer, 
  W. 
  A., 
  Kitchen, 
  S. 
  F., 
  and 
  Lloyd, 
  W. 
  

  

  1932. 
  Vaccination 
  against 
  yellow 
  fever 
  with 
  immune 
  serum 
  and 
  virus 
  fixed 
  

   for 
  mice. 
  Journ. 
  Exp. 
  Med., 
  vol. 
  55, 
  p. 
  945. 
  

  

  