title: Frequency of histopathological changes in Howler monkeys ( Alouatta sp.) naturally infected with yellow fever virus in Brazil.
abstract: BACKGROUND
  Due to the importance that Howler monkeys have on the yellow fever (YF) epidemiological sylvatic cycle in Brazil, more accurate morphological diagnostic criteria needs to be established, especially considering the differences that may exist between the genera of Brazilian non-human primates (NHPs) involved in yellow fever virus (YFV) epizootics.
  
  
  METHODS
  Records of YF epizootics in NHPs in Brazil between 2007 and 2009 were obtained from the Brazilian Ministry of Health database to select YF positive (n=98) Howler monkeys (Alouatta sp.) for this study. The changes described in the histopathological reports were categorized by organ and their frequencies calculated.
  
  
  RESULTS
  The most frequent lesions observed in the animals with YF were hepatocyte apoptosis (Councilman body formation), midzonal hepatocyte necrosis, steatosis, liver hemorrhage, inflammatory mononuclear cell infiltration of the liver, renal acute tubular necrosis and interstitial nephritis. Midzonal hepatocyte necrosis, steatosis and hemorrhage presented positive correlations with apoptosis of hepatocytes, suggesting strong YFV pathogenic effect association; they were also the main histopathological changes in the Alouatta sp. A pronounced negative correlation between apoptosis of hepatocytes and hepatic mononuclear cell infiltration pointed to significant histopathological differences between YFV infection in Howler monkeys and humans.
  
  
  CONCLUSIONS
  The results warn that NHPs may exhibit different response patterns following YFV infection and require a more careful diagnosis. Presumptive diagnosis based on primate histopathological lesions may contribute to public health service control.
authors.affiliation: Departamento de Vigilância das Doenças Transmissíveis, Secretaria de Vigilância em Saúde, Ministério da Saúde, Brasília, Distrito Federal, Brazil.
authors.forename: Silvana Gomes
authors.initials: SG
authors.lastname: Leal
authors.affiliation: Departamento de Vigilância das Doenças Transmissíveis, Secretaria de Vigilância em Saúde, Ministério da Saúde, Brasília, Distrito Federal, Brazil.
authors.forename: Alessandro Pecego Martins
authors.initials: AP
authors.lastname: Romano
authors.affiliation: Faculdade de Agronomia e Veterinária, Universidade de Brasília, Brasília, Distrito Federal, Brazil.
authors.forename: Rafael Veríssimo
authors.initials: RV
authors.lastname: Monteiro
authors.affiliation: Faculdade de Agronomia e Veterinária, Universidade de Brasília, Brasília, Distrito Federal, Brazil.
authors.forename: Cristiano Barros de
authors.initials: CB
authors.lastname: Melo
authors.affiliation: Instituto Evandro Chagas, Secretaria de Vigilância em Saúde, Ministério da Saúde, Belém, Pará, Brazil.
authors.forename: Pedro Fernando da Costa
authors.initials: PF
authors.lastname: Vasconcelos
authors.affiliation: Faculdade de Agronomia e Veterinária, Universidade de Brasília, Brasília, Distrito Federal, Brazil.
authors.forename: Márcio Botelho de
authors.initials: MB
authors.lastname: Castro
mesh_terms: D000508:Alouatta / Q000821:virology*; D000818:Animals; D001938:Brazil / Q000453:epidemiology; D004196:Disease Outbreaks / Q000662:veterinary*; D008992:Monkey Diseases / Q000453:epidemiology / Q000473:pathology*; D015004:Yellow Fever / Q000453:epidemiology / Q000473:pathology / Q000662:veterinary*