Spatial Epidemiology of E scherichia coli O 157: H 7 in Dairy Cattle in Relation to Night Roosts Of S turnus vulgaris ( E uropean Starling) in O hio, USA (2007–2009)

Summary The goal of our study was to use spatial scan statics to determine whether the night roosts of E uropean starlings ( S turnus vulgaris ) act as point sources for the dissemination of E scherichia coli O 157: H 7 among dairy farms. From 2007 to 2009, we collected bovine faecal samples ( n  = 9000) and starling gastrointestinal contents ( n  = 430) from 150 dairy farms in northeastern O hio, USA . Isolates of E . coli O 157: H 7 recovered from these samples were subtyped using multilocus variable‐number tandem repeat analysis ( MLVA ). Generated MLVA types were used to construct a dendrogram based on a categorical multistate coefficient and unweighted pair‐group method with arithmetic mean ( UPGMA ). Using a focused spatial scan statistic, we identified statistically significant spatial clusters among dairy farms surrounding starling night roosts, with an increased prevalence of E . coli O 157: H 7‐positive bovine faecal pats, increased diversity of distinguishable MLVA types and a greater number of isolates with MLVA types from bovine‐starling clades versus bovine‐only clades. Thus, our findings are compatible with the hypothesis that starlings have a role in the dissemination of E . coli O 157: H 7 among dairy farms, and further research into starling management is warranted.