|SANCHEZ-INGUNZA, ROXANA - Rsi Poultry Veterinary Consulting|
|PULIDO-LANDINEZ, MARTHA - Mississippi State University|
Submitted to: American Association of Avian Pathologists
Publication Type: Abstract Only
Publication Acceptance Date: 6/22/2021
Publication Date: 7/1/2021
Citation: Sanchez-Ingunza, R., Pulido-Landinez, M., Guard, J.Y. 2021. Genetic characterization of Salmonella Enteritidis recovered from chicken samples collected by the USDA FSIS in Mississippi between 2016 and 2020. American Association of Avian Pathologists. https://pheedloop.com/EVESOUDKILPPY/site/sessions/?id=SESVARPD89FKJ87AH.
Interpretive Summary: The study highlights specific genetic characteristics in Salmonella enterica serovar Enteritidis (SE) currently prevalent in poultry products in Mississippi, and the information can potentially be used to target prevention strategies. Two distinct lineages were evaluated, namely a PT13a lineage common in the United States and one which clustered with the PT4 lineage first observed overseas. Antibiotic resistances were determined for each lineage. SE from poultry in Mississippi were highly similar to the PT13a reference strain obtained from mice. Resistance to antibiotics was reduced and not associated with plasmids. Overall, whole genome sequencing data from the Food Safety and Inspection Service was successfully used for the identification of other gene targets for pathogen control, namely IncX1 and Type IV secretion system genes.
Technical Abstract: Salmonella enterica subsp enterica serovar Enteritidis (SE), is the leading cause of salmonellosis in humans in the United States. Since 2013, an increasing trend of foodborne illness linked to chicken and caused by this serovar has been reported by the National Outbreak Reporting System (NORS) from the Center for Disease Control and Prevention (CDC) in the U.S. In addition, SE is one of the most common serovars detected in chickens (NVSL - USDA APHIS, 2018) and the control of this microorganism in poultry represents a challenge nowadays when birds are raised with none or reduced use of antibiotics. The purpose of this study was to improve the understanding of SE infecting poultry and ultimately guide Salmonella control practices in Mississippi. The genetic characteristics of 81 SE isolates collected by the USDA Food Safety Inspection Service from Mississippi poultry establishments between 2016 and 2020 were evaluated in comparison with the SE Phage Type 4 (PT4) strain P125109 and the U.S. mouse origin SE Phage Type 13a (PT13a) NZ_CP022003 reference sequences. The phylogenetic analysis showed the SE strains from Mississippi clustered into two distinct phylogenetic clades. Clade 1 was the most closely related to the SE PT13a reference strain while Clade 2 clustered together with the SE PT4 reference strain. Based on sample source, most of the SE isolates recovered from comminuted chicken samples were located in Clade 1, while most of the samples recovered from carcass rinses were located in Clade 2. A detailed description of relevant features in the SE Mississippi strains, as well as the predicted antibiotic resistance profiles and replicon or plasmid content is discussed. The study highlights specific genetic characteristics in SE currently prevalent in poultry products in Mississippi which can potentially be used to target prevention strategies.