title: Utilizing a combination of molecular and spatial tools to assess the effect of a public health intervention.
abstract: Until recently New Zealand had one of the highest rates of human campylobacteriosis reported by industrialized countries. Since the introduction of a range of control measures in the poultry production chain a reduction in human cases of around 50% has been observed nationwide. To inform risk managers a combination of spatial, temporal and molecular tools - including minimum spanning trees, risk surfaces, rarefaction analysis and dynamic source attribution modelling - was used in this study to formally evaluate the reduction in disease risk that occurred after the implementation of control measures in the poultry industry. Utilizing data from a sentinel surveillance site in the Manawatu region of New Zealand, our analyses demonstrated a reduction in disease risk attributable to a reduction in the number of poultry-associated campylobacteriosis cases. Before the implementation of interventions poultry-associated cases were more prevalent in urban than rural areas, whereas for ruminant-associated cases the reverse was evident. In addition to the overall reduction in prevalence, this study also showed a stronger intervention effect in urban areas where poultry sources were more dominant. Overall a combination of molecular and spatial tools has provided evidence that the interventions aimed at reducing Campylobacter contamination of poultry were successful in reducing poultry-associated disease and this will inform the development of future control strategies.
authors.affiliation: mEpiLab, Hopkirk Research Institute, Massey University, Private Bag 11 222, Palmerston North 4442, New Zealand. petra@epi-interactive.com
authors.forename: P
authors.initials: P
authors.lastname: Muellner
authors.forename: J C
authors.initials: JC
authors.lastname: Marshall
authors.forename: S E F
authors.initials: SE
authors.lastname: Spencer
authors.forename: A D
authors.initials: AD
authors.lastname: Noble
authors.forename: T
authors.initials: T
authors.lastname: Shadbolt
authors.forename: J M
authors.initials: JM
authors.lastname: Collins-Emerson
authors.forename: A C
authors.initials: AC
authors.lastname: Midwinter
authors.forename: P E
authors.initials: PE
authors.lastname: Carter
authors.forename: R
authors.initials: R
authors.lastname: Pirie
authors.forename: D J
authors.initials: DJ
authors.lastname: Wilson
authors.forename: D M
authors.initials: DM
authors.lastname: Campbell
authors.forename: M A
authors.initials: MA
authors.lastname: Stevenson
authors.forename: N P
authors.initials: NP
authors.lastname: French
mesh_terms: D000818:Animals; D015373:Bacterial Typing Techniques; D001499:Bayes Theorem; D002169:Campylobacter Infections / Q000453:epidemiology* / Q000662:veterinary; D016123:Campylobacter jejuni / Q000235:genetics*; D005838:Genotype; D006801:Humans; D008954:Models, Biological; D017720:Molecular Epidemiology / Q000379:methods*; D058885:Multilocus Sequence Typing; D009520:New Zealand / Q000453:epidemiology; D011200:Poultry; D011201:Poultry Diseases / Q000382:microbiology; D018570:Risk Assessment / Q000379:methods*; D012424:Rural Population; D018571:Sentinel Surveillance; D014505:Urban Population