Evaluating Wildlife as a Potential Source of Salmonella serotype Newport ( JJPX 01.0061) Contamination for Tomatoes on the Eastern Shore of Virginia

Summary Eastern S hore of V irginia red, round tomatoes contaminated with S almonella serotype N ewport pattern JJPX 01.0061 have been a source of several multistate outbreaks within the last 10 years. No source of the contamination has yet been identified. The goal of this study was to evaluate wildlife as a potential source of contamination. Faecal samples from deer, turtles and birds were collected between N ovember 2010 and J uly 2011 from seventeen locations on the E astern S hore of V irginia. A total of 262 samples were tested for the presence of S almonella using an enzyme‐linked immunosorbent assay ( ELISA ). A total of 23 (8.8%) samples tested positive for S almonella spp. and were further characterized by serotyping and pulsed‐field gel electrophoresis ( PFGE ) subtyping. Overall, twelve serotypes were identified, including S almonella serotype J aviana, another common serotype associated with tomato‐related outbreaks. Only one avian sample collected in July 2011 was determined to be positive for S .  N ewport pattern 61. This sample was collected from the ground at a site where birds, mostly gulls, were congregating. Although many of the avian samples from this site were dry, the site yielded eleven positive S almonella samples. This suggests that certain S almonella serotypes may persist in the environment despite extreme conditions. The recovery of one N ewport pattern 61 isolate alone does not yield much information regarding the environmental reservoirs of this pathogen, but when combined with other data including the recovery of several isolates of J aviana from birds, it suggests that birds might be a potential source of S almonella contamination for tomatoes on the E astern S hore.