The epidemiology of Salmonella transmission in chicken meat
AuthorCrabb, Helen Kathleen
Document TypePhD thesis
Access StatusThis item is embargoed and will be available on 2020-07-12.
© 2018 Dr. Helen Kathleen Crabb
A longitudinal study was conducted between January 2013 and September 2014 in a vertically integrated chicken meat enterprise under commercial farming conditions. Using methods routinely used for Salmonella surveillance in poultry production systems, environmental sampling was conducted in two generations (parent and broiler) at multiple locations within the production system. Data was collected on all product movements during the study period and social network analysis was used to describe product movements and identify locations for the potential introduction and dissemination of Salmonella. The results showed that the structure of a vertically integrated enterprise enhanced the transmission of Salmonella between poultry generations and locations, even at a very low prevalence, and that the hatchery was a critical point of amplification. The use of phenotyping (phage typing) and genotyping (MLVA) tools were not sufficient in the absence of good sampling (methodology or intensity) or epidemiological evidence to determine the source of introduction or dissemination within this complex environment. Whole genome sequencing allowed the genetic relatedness of the S. Typhimurium isolates to be elucidated and confirmed that transmission was occurring between generations within the enterprise with little to no change. Diversity and cluster analysis findings suggest that these salmonellae were not a significant source of infection to the human population during the study period.
KeywordsSalmonella; Salmonella Typhimurium; epidemiology; poultry; chicken meat; public health; social network analysis; whole genome sequencing; MLVA; phage typing
- Click on "Export Reference in RIS Format" and choose "open with... Endnote".
- Click on "Export Reference in RIS Format". Login to Refworks, go to References => Import References