The role of rats and mice in dissemination of pathogens and antimicrobial resistance

Rats and mice are ubiquitous in urban and rural environments, are in contact with sewage effluents, have a generalist and opportunistic diet and interact frequently with human wastes. While they cause considerable physical damage to buildings and utilities, they pose even more serious risks to public health by spreading disease. They are known to carry a wide range of pathogens including many species of bacteria, viruses, protozoa and helminths. In addition, a number of recent studies have found that rodents harbour significant antimicrobial resistance (AMR) bacteria including multidrug-resistance Enterobacteriaceae and methicillin-resistance Staphylococcus spp. To exacerbate the problem further, surveillance work undertaken by the members of our supervisory team in 2019 revealed that 93% and 61% of house mice and rats carry at least one rodenticide resistance gene respectively - among rats, nearly half have inherited the gene from both parents, the most severe form of resistance. Despite these known and emerging threats, the role of rodents as reservoirs and/or vectors of pathogen, AMR as well as the extent of their resistance to rodenticide is still poorly understood. And, this is where this PhD programme comes in - we propose to understand the variation in the distributions and dispersal dynamics of rodent-borne pathogens, AMR and rodenticide resistance in urban, suburban and rural settings utilising modern techniques and technologies. Notably, this project will develop and apply cutting-edge molecular techniques and bioinformatics to identify pathogens, AMR and rodenticide resistance in rodents. Another important and unique aspect of our project is our UK-wide samples obtained from the existing network of collaborating pest controllers coordinated by Action Groups including Rodenticide Resistance Action Committee (RRAC) and the Campaign for Responsible Rodenticide Use (CRRU) with whom our Supervisory Team has direct links. Access to a large number of samples from around the UK and a variety of different ecological niches, combined with the novel high through put molecular analysis, will allow a thorough analysis of any correlation of rodent niche with pathogen and AMR carriage and also rodenticide resistance.