Bettridge, Judy M.

Brena, M.C.

Christley, Robert M.

Collins, M.

Dessie, Tadelle

Mekkonen, Y.

Tessema, T.S.

CGSpace

Y.	  Mekkonen1,	  M.C.	  Brena2,	  R.	  Christley2,	  J.M.	  Be8ridge2,	  	  M.	  Collins2,	  T.	  Dessie3,	  T.S.	  Tessema1	  	  1College	  of	  Veterinary	  Medicine	  and	  Agriculture,	  Addis	  Ababa	  University,	  Ethiopia	  2InsKtute	  of	  InfecKon	  and	  Global	  Health,	  Liverpool	  University,	  UK	  3InternaKonal	  Livestock	  Research	  InsKtute,	  Addis	  Ababa,	  Ethiopia	  	  Introduc*on	  	  •  Poultry	  in	  Ethiopia	  are	  predominantly	  indigenous	  chicken	  ecotypes	  maintained	  under	  rural,	  	  tradiKonal	  scavenging	  or	  semi-­‐scavenging	  systems.	  	  •  A	  greater	  demand	  for	  poultry	  and	  poultry	  products	  has	  seen	  growth	  in	  urban	  and	  peri-­‐urban	  flocks	  under	  semi-­‐intensive	  management	  systems.	  Such	  flocks	  oTen	  include	  exoKc	  and	  exoKc/indigenous	  hybrid	  birds.	  	  •  Studies	  have	  idenKfied	  poultry,	  ca8le,	  sheep,	  goats,	  pigs,	  cat	  and	  dogs	  as	  asymptomaKc	  carriers	  of	  C.jejuni	  and	  C.coli	  in	  Ethiopia,	  with	  a	  higher	  prevalence	  of	  bacteria	  in	  chickens	  and	  poultry	  meat	  compared	  with	  other	  farm	  animal	  and	  meat	  products.	  •  Shared	  environment/co-­‐habitaKon	  by	  humans	  and	  chickens	  presents	  a	  putaKve	  risk	  factor	  for	  zoonoKc	  Campylobacter	  infecKon.	  •  This	  study	  invesKgates	  whether	  the	  intensificaKon	  of	  poultry	  producKon	  systems	  in	  Ethiopia	  may	  	  impact	  on	  the	  epidemiology	  and	  ecology	  of	  Campylobacter,	  and	  considers	  the	  potenKal	  implicaKons	  of	  this	  changing	  dynamic	  for	  human	  health	  in	  the	  country.	  	  	  	  Methodology	  	  •  A	  cross-­‐secKonal	  study	  was	  conducted	  between	  October	  2012	  to	  April	  2013	  in	  3	  woredas	  (administraKve	  regions),	  	  Horro,	  Jarso	  and	  Debre	  Zeit	  (within	  the	  Ada’a	  woreda)	  in	  the	  Oromia	  region	  of	  Ethiopia.	  	  	  •  Sampling	  was	  conducted	  in	  4	  villages	  in	  each	  of	  the	  two	  rural	  districts.	  Twenty	  households	  were	  randomly	  selected	  	  from	  a	  list	  of	  farmers	  in	  each	  village,	  provided	  by	  local	  development	  agents.	  Households	  were	  excluded	  from	  the	  study	  if	  they	  did	  not	  own	  at	  least	  two	  chickens.	  A	  further	  60	  backyard	  flocks	  and	  20	  intensive/	  semi-­‐intensive	  farms	  within	  the	  Debre	  Zeit	  town	  area	  were	  purposively	  selected	  for	  sampling	  during	  the	  same	  Kme	  period	  as	  the	  cross-­‐secKonal	  study.	  	  •  Disposable	  fabric	  overshoes	  (boot	  socks)	  were	  worn	  and	  used	  to	  collect	  samples	  of	  faeces	  on	  the	  ground	  (Fig.2)	  by	  	  walking	  through	  the	  household/farm	  environment.	  •  Bacterial	  DNA	  extracKon	  from	  collected	  faecal	  material	  was	  extracted	  using	  a	  commercial	  DNA	  extracKon	  kit	  .	  •  DNA	  isolates	  were	  analysed	  using	  a	  PCR	  assay	  specific	  for	  the	  genus	  Campylobacter	  on	  the	  basis	  of	  16s	  rRNA	  sequences	  and	  further	  confirmed	  to	  species	  level	  (C.jejuni	  and	  C.coli)	  by	  mulKplex	  PCR	  based	  on	  differences	  in	  the	  lpxA	  gene.	  •  MulKvariate	  regression	  modelling	  was	  used	  to	  compare	  the	  prevalence	  of	  Campylobacter	  carriage	  rate	  of	  chickens	  reared	  in	  different	  geographical	  areas	  and	  to	  compare	  proporKon	  of	  posiKve	  samples	  among	  chickens	  from	  the	  same	  area	  reared	  under	  different	  producKon	  systems.	  	  	  Results	  •  Boot	  sock	  samples	  (n=239)	  were	  collected	  from	  Horro	  (n=79),	  Jarso	  (n=80)	  and	  Debre	  Zeit	  (n=80).	  	  •  Prevalence	  of	  Campylobacter	  detected	  across	  the	  three	  sampled	  regions	  was	  18.41%	  (44/239).	  Of	  these,	  16	  isolates	  could	  be	  speciated	  using	  mulKplex	  PCR,	  all	  of	  which	  were	  idenKfied	  as	  C.jejuni.	  •  Results	  from	  the	  mulKvariate	  model	  (Table.1)	  suggested	  that	  peri-­‐urban	  flocks	  were	  more	  likely	  to	  be	  Campylobacter	  posiKve	  (Odds	  RaKo	  15.6,	  95%	  C.I.	  6.0	  –	  40.2).	  Flocks	  which	  consisted	  only	  of	  Rhode	  Island	  Red	  or	  RIR	  hybrids	  were	  also	  at	  greater	  risk	  (Odds	  RaKo	  5.0,	  95%	  C.I.	  1.0-­‐24.9)	  whilst	  the	  Cobb	  500	  birds,	  which	  were	  only	  kept	  in	  intensive	  or	  semi-­‐intensive	  farms	  tended	  to	  be	  at	  slightly,	  although	  not	  significantly,	  greater	  risk.	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  Table.	  1.	  Results	  from	  mulKvariate	  model.	  	  Conclusions	  •  The	  greatest	  risk	  factor	  idenKfied	  in	  our	  study	  for	  Campylobacter	  infecKon	  in	  chicken	  flocks	  was	  locaKon	  in	  the	  peri-­‐urban	  area,	  where	  many	  farms	  are	  starKng	  to	  intensify	  their	  producKon	  systems.	  •  Whilst	  more	  intensively	  farmed	  flocks	  appear	  at	  increased	  risk,	  it	  is	  of	  parKcular	  concern	  that	  tradiKonally	  managed	  flocks	  of	  indigenous	  birds	  in	  nearby	  areas	  also	  have	  high	  rates	  of	  carriage.	  These	  may	  potenKally	  contaminate	  the	  home	  environment	  of	  smallholder	  farmers,	  increasing	  risks	  to	  human	  health.	  •  More	  research	  needs	  to	  be	  done	  to	  evaluate	  the	  effect	  of	  changing	  producKon	  systems	  on	  the	  epidemiology	  of	  Campylobacter	  and	  idenKfy	  ways	  to	  minimise	  risks	  to	  health	  Detection of Campylobacter carriage rate in different poultry production systems in Ethiopia •  Campylobacter	  bacteria	  are	  a	  major	  cause	  of	  foodborne	  diarrhoeal	  illness	  in	  humans	  and	  represent	  the	  main	  cause	  of	  infant	  enteric	  disease	  in	  developing	  countries.	  •  Campylobacter	  is	  an	  important	  zoonosis,	  with	  infecKon	  occurring	  mainly	  through	  ingesKon	  of	  contaminated	  food	  and	  water,	  or	  direct	  contact	  with	  contaminated	  food	  animal	  species	  or	  their	  carcasses.	  •  The	  bacteria	  are	  typically	  spiral,	  S-­‐shaped	  or	  curved	  rods	  (Fig.1).	  Within	  the	  17	  species	  and	  6	  subspecies	  of	  the	  genus,	  C.jejuni	  and	  C.coli	  are	  the	  most	  frequently	  reported	  in	  human	  disease.	  	  ProporKon	  of	  flocks	  tested	  posiKve	  for	  Campylobacter,	  showing	  locaKon,	  bird	  and	  farm	  type.	  Points	  are	  scaled	  relaKve	  to	  the	  number	  of	  flocks	  of	  each	  type	  tested.	  	  	  Campylobacter	  Variable	   Levels	   coefficient	   se	   OR	   95%	  C.I.	   P	  Intercept	   -­‐3.10	   0.39	   0.04	   0.02	   -­‐	   0.10	   0.000	  Area	   Rural	   reference	  Peri-­‐urban	   2.74	   0.48	   15.56	   6.03	   -­‐	   40.15	   0.000	  Flock	  type	   Backyard	  -­‐	  Indigenous	   reference	  Backyard	  -­‐	  Mixed	   -­‐1.11	   0.83	   0.33	   0.06	   -­‐	   1.67	   0.180	  Backyard	  –	  RIR/Hybrid	   1.61	   0.82	   5.02	   1.02	   -­‐	   24.87	   0.048	  Housed	  -­‐	  Cobb	  500	   0.76	   0.55	   2.15	   0.73	   -­‐	   6.29	   0.163	  CHICKEN	  HEALTH	  4	  DEVELOPMENT	  Fig.	  2.	  Boot	  sock	  sampling	  of	  chicken	  faeces.	  Source:	  Farming	  UK	  	  Fig.	  1.	  Electron	  micrograph	  of	  Campylobacter	  jejuni.	  Source:	  Roslin	  InsKtute	  

Detection of Campylobacter carriage rate in different poultry production systems in Ethiopi

https://cgspace.cgiar.org/bitstream/10568/64989/1/DetectionCampylobacter.pdf

Detection of Campylobacter carriage rate in different poultry production systems in Ethiopi

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