Modeling the Transmission of ESBL and AmpC-Producing Escherichia coli in Denmark: A Compartmental and Source Attribution Approach

Extended-spectrum cephalosporin-resistant Escherichia coli (ESC-EC) poses a significant public health concern, with its presence increasingly detected in healthy humans and various animal species. This study explores the transmission dynamic of ESC-EC within the Danish population as well as the transmission impact of a range of food and animal sources. We developed a compartmental model encompassing farmers, pet owners, and the general population. Additionally, we applied an established source attribution model to estimate the contributions to the transmission of different sources using Danish surveillance data on the distribution of resistance genes in E. coli. Our findings highlight the central role of human-to-human transmission while also showing the significant contributions of food and animal sources to the spread of ESC-EC in sporadic human infections. Imported food, pets, and livestock were estimated to contribute importantly to human infections. The results emphasize the complexity of ESC-EC transmission dynamics and the critical value of employing a One Health approach in modeling disease transmission and in the development of targeted intervention strategies.