Prevalence and Spatial Distribution of Salmonella Infections in the Pennsylvania Raccoon (Procyon lotor)

Abstract

A study was conducted to determine the prevalence and spatial distribution of Salmonella infection in Pennsylvania raccoons (Procyon lotor), common wildlife mammals known to occupy overlapping habitats with humans and domestic food animals. The Pennsylvania Game Commission provided a total of 371 raccoon intestinal samples from trapped and road-killed raccoons collected between May and November 2011. Salmonella was isolated from the faeces of 56 (15.1%) of 371 raccoons in 35 (54%) of 65 counties across Pennsylvania. The five most frequently isolated serotypes were Newport (28.6%), Enteritidis (19.6%), Typhimurium (10.7%), Braenderup (8.9%) and Bareilly (7.1%). Pulsed-field gel electrophoresis (PFGE) analysis of the Salmonella isolates and subsequent comparison to the Pennsylvania Department of Health human Salmonella PFGE database revealed 16 different pulsetypes in Salmonella isolates recovered from raccoons that were indistinguishable from pulsetypes of Salmonella collected from clinically ill humans during the study period. The pulsetypes of seven raccoon Salmonella isolates matched those of 56 human Salmonella isolates by month and geographical region of sample collection. Results from Clustered Regularly Interspaced Short Palindromic Repeats and Multi-Virulence Locus Sequence Typing (CRISPR-MVLST) analysis corroborated the PFGE and serotyping data. The findings of this study show that several PFGE pulsetypes of Salmonella were shared between humans and raccoons in Pennsylvania, indicating that raccoons and humans might share the same source of Salmonella.

Salmonellosis detection and evidence of antibiotic resistance in an urban raccoon population in a highly populated area, Costa Rica

“…Antimicrobial resistance in raccoon Salmonella isolates from our study yielded prevalences similar to other studies (Jardine et al, ; Lee et al, ; Very et al, ). However, only Lee et al, previously reported resistance to nalidixic acid without resistance to ciprofloxacin in Salmonella from raccoons.…”

“…Previous reports from varying temperate zone urban, rural and natural environments have provided contradictory results as to the prevalence of Salmonella serovars in raccoons (Compton et al, ; Jardine et al, ; Lee et al, ; Rainwater et al, ; Very et al, ). In tropical urban settings, we found S. Hartford to have the highest prevalence followed by S. Typhimurium and S. Bovismorbificans.…”

“…Concurrently, other authors have reported S . Hartford as less prevalent or even absent (Bondo et al, a; Lee et al, ; Very et al, ; White, Watson, Hoff, & Bigler, ). This contrasts with our findings, where S .…”

“…Very et al showed that 16 different PFGE isolates from raccoons were similar to those recovered from clinically ill patients in Pennsylvania, USA. We did not perform a PFGE analysis of our raccoon samples; therefore, it is not possible to establish how many serovars are potentially involved in an exchange or overlap of serovars (Very et al, ). Certainly, in our study there is a significant similarity in the number of serovars isolated in raccoons and those reported in humans in the study area (47% national cases; INCIENSA, ).…”

Prevalence of Group I Salmonella Kentucky in domestic food animals from Pennsylvania and overlap with human clinical CRISPR sequence types

“…A CRISPR‐based subtyping scheme, CRISPR‐multi‐virulence locus sequence typing (MVLST), is highly discriminatory between unrelated isolates and this has been demonstrated in multiple serovars (Almeida, Medeiros, Rodrigues, Allard, & Falcão, ; DiMarzio, Shariat, Kariyawasam, Barrangou, & Dudley, ; Liu, Barrangou, et al, ; Liu, Kariyawasam, et al, ; Shariat, DiMarzio, et al, ; Shariat, Kirchner, et al, ; Shariat, Sandt, DiMarzio, Barrangou, & Dudley, 2013; Very et al, ; Vosik, Tewari, Dettinger, & M'ikanatha, & Shariat, ). In a previous study from our group, CRISPR‐MVLST was used to analyse human clinical samples of Salmonella Kentucky from Pennsylvania.…”