title: Carrier status for Listeria monocytogenes and other Listeria species in free range farm and market healthy indigenous chickens and ducks.
abstract: BACKGROUND
  Listeria organisms are documented to be zoonotic; one of the sources of infection is the domestic fowl where it could occur as in apparent infection. The carriage of Listeria monocytogenes and other Listeria in indigenous birds has not been documented in Kenya.
  
  
  OBJECTIVE
  To establish whether healthy looking indigenous chickens and ducks could be carriers of Listeria monocytogenes and other Listeria species.
  
  
  METHODS
  Field survey of indigenous chickens and ducks in three districts of Kenya.
  
  
  METHODS
  Embakasi and Dagoreti divisions in Nairobi district; Athi river division in Machakos district; and Ngong division in Kajiado district, in Kenya.
  
  
  METHODS
  One hundred and thirty six indigenous chickens and 39 ducks reared under free range scavenging system in Nairobi, Machakos and Kajiado districts, in Kenya, were sampled.
  
  
  METHODS
  In surveying the birds, the cloacal and pharyngeal swabs were taken from each bird separately using sterile cotton--tipped applicator swabs. The swabs in saline were transported in a coolbox to the laboratory for bacterial isolation and characterization.
  
  
  METHODS
  None (only compared farmed and the traded birds).
  
  
  METHODS
  Isolation of Listeria species and pathogenicity of Listeria isolates.
  
  
  RESULTS
  Two Listeria monocytogenes and seven other Listeria species were recovered from the oropharyngeal swab samples of farm and market chickens but none from respective cloacal swabs. No Listeria was recovered from either oropharyngeal or cloacal swabs of farmed duck and slaughter chickens. Traded chickens yielded more Listeria isolates as compared to farmed chickens.
  
  
  CONCLUSIONS
  This study shows that indigenous chickens in Kenya are carriers of Listeria monocytogenes and other Listeria species.
authors.affiliation: Department of Veterinary Pathology, Microbiology and Parasitology, University of Nairobi, P.O. Box 29053, Nairobi, Kenya.
authors.forename: L W
authors.initials: LW
authors.lastname: Njagi
authors.forename: P G
authors.initials: PG
authors.lastname: Mbuthia
authors.forename: L C
authors.initials: LC
authors.lastname: Bebora
authors.forename: P N
authors.initials: PN
authors.lastname: Nyaga
authors.forename: U
authors.initials: U
authors.lastname: Minga
authors.forename: J E
authors.initials: JE
authors.lastname: Olsen
mesh_terms: D000818:Animals; D002353:Carrier State; D002645:Chickens / Q000382:microbiology*; D002988:Cloaca / Q000382:microbiology; D004372:Ducks / Q000382:microbiology*; D005516:Food Microbiology; D007630:Kenya; D008087:Listeria / Q000302:isolation & purification*; D008088:Listeriosis / Q000635:transmission*; D009960:Oropharynx / Q000382:microbiology