title: The necrophagous fly anthrax transmission pathway: empirical and genetic evidence from wildlife epizootics.
abstract: Early studies confirmed Bacillus anthracis in emesis and feces of flies under laboratory conditions, but there is little empirical field evidence supporting the roles of flies in anthrax transmission. We collected samples during outbreaks of anthrax affecting livestock and native and exotic wildlife on two ranches in West Texas (2009-2010). Sampling included animal carcasses, maggots, adult flies feeding on or within several meters of carcasses, and leaves from surrounding vegetation. Microbiology and PCR were used to detect B. anthracis in the samples. Viable B. anthracis and/or PCR-positive results were obtained from all represented sample types. Genetic analysis of B. anthracis samples using multilocus variable number tandem repeat analysis (MLVA) confirmed that each ranch represented a distinct genetic lineage. Within each ranch, we detected the same genotype of B. anthracis from carcasses, maggots, and adult flies. The results of this study provide evidence supporting a transmission cycle in which blowflies contaminate vegetation near carcasses that may then infect additional browsing animals during anthrax outbreaks in the shrubland environment of West Texas.
authors: 1 Spatial Epidemiology & Ecology Research Laboratory, Department of Geography, University of Florida , Gainesville, Florida.
authors: Jason K
authors: JK
authors: Blackburn
authors: Matthew
authors: M
authors: Van Ert
authors: Jocelyn C
authors: JC
authors: Mullins
authors: Ted L
authors: TL
authors: Hadfield
authors: Martin E
authors: ME
authors: Hugh-Jones
mesh_terms: D000818:Animals; D000881:Anthrax / Q000453:epidemiology / Q000635:transmission* / Q000662:veterinary*; D001408:Bacillus anthracis / Q000235:genetics / Q000302:isolation & purification*; D004175:Diptera / Q000382:microbiology*; D004196:Disease Outbreaks / Q000662:veterinary*; D014644:Genetic Variation; D005838:Genotype; D007303:Insect Vectors / Q000502:physiology; D058751:Livestock / Q000382:microbiology*; D018515:Plant Leaves / Q000382:microbiology; D012418:Ruminants / Q000382:microbiology*; D013781:Texas / Q000453:epidemiology
keywords: Anthrax; Bacillus anthracis; Disease ecology; Pathogen transmission; Phylogenetics