Animal and zoonotic bacterial pathogens - Mark Stevens

 Research in the Stevens laboratory aims to improve food safety and enhance animal health by defining the role of bacterial and host factors during Salmonella, Campylobacter and Escherichia coli infections. These agents collectively cause an estimated 174 million cases of acute diarrhoea in humans and 80,000 deaths worldwide each year and infections can be complicated by life-threatening sequelae. Human infections are frequently acquired via the food chain and environment from farm animals and control of the agents in reservoir hosts is expected to reduce the incidence of foodborne disease.

Toward this aim, his team use genetic approaches to identify factors that influence bacterial persistence and pathogenesis. For example, they applied transposon-directed insertion-site sequencing to assign roles to thousands of Salmonella genes in intestinal colonisation of calves, pigs and chickens, providing valuable information for the design of vaccines with minimal animal use(1).

From the host perspective, they have used genome-wide association studies to identify regions of the chicken genome that influence resistance to Campylobacter to inform selective breeding(2). Having identified factors influencing virulence the team use molecular approaches to dissect their mode of action.

Ongoing research aims to evaluate novel glycoconjugate vaccines, unravel the spatiotemporal dynamics of spread of Salmonella in cattle and understand the dynamics of transfer of antimicrobial resistance genes in gut microbiota.

Award-winning work to reduce, refine or replace animals in research is also performed, including in surgical models of enteritis.

1. Chaudhuri RR et al. 2013. Comprehensive assignment of roles for Salmonella Typhimurium genes in intestinal colonisation of food-producing animals. PLoS Genetics 9:e1003456.
2. Psifidi A et al. 2016. The genomic architecture of resistance to Campylobacter jejuni intestinal colonisation in chickens. BMC Genomics 17:293.