A comprehensive assessment of the impact of Campylobacter positive broilers on human infection – from farm to molecular epidemiology

The overall aim of the project is to provide scientific grounds for better surveillance and monitoring program for campylobacteriosis in Sweden. Campylobacter is the most common cause of bacterial gastroenteritis in humans and the most notified zoonosis in the European Union. The incidence of campylobacteriosis has increased in Sweden partly due to outbreaks traced to domestically produced chicken meat. These infections have led to substantial economic losses to the society, to the individuals, and to the industry. In order to decrease the incidence, more knowledge is needed on the epidemiology of the infection, importance of chicken as a source of infection, and motivations to achieve a low prevalence in the primary production. Here, we propose to perform whole genome sequencing on Campylobacter jejuni isolates from broilers throughout a year to study the genetic diversity, antimicrobial resistance, the transmission dynamics within and between farms, and associated factors such as management and season. We will also genotype a subset of C. jejuni isolates from human cases to assess the magnitude of impact on public health by broilers, and further perform a time series analysis to evaluate the temporal association. Lastly, we will interview broiler farmers, industry representatives, health care professionals and consumers to gather qualitative information on their experiences regarding the recent outbreaks as well as suggestions for improvements.