The association between foodborne quinolone-nonsusceptible Salmonella and hospitalized salmonellosis cases in China

There is significant concern over the emergence and spread of antibiotic-resistant bacteria from foodborne sources but little research has been done to quantify the effect this has on human health and on health systems. This dissertation evaluates the association between human health and antibiotic-resistant bacteria found in food products for human consumption. Specifically, it examines the association between the costs for hospitalized cases of quinolone-nonsusceptible salmonellosis and the prevalence of quinolone-nonsusceptible Salmonella found in freshwater aquaculture products in the south coastal region of China.;The first study is a literature review and qualitative analysis of food safety policies and practices in aquaculture production in Guangdong Province. The next two studies determine the prevalence of quinolone-susceptible and -nonsusceptible Salmonella in food products from Guangdong and specifically in farmed freshwater finfish. The following two studies quantify the difference between quinolone-susceptible and -nonsusceptible salmonellosis in terms of lengths of hospital stay and hospital costs in Guangdong and Hong Kong. Results from these studies and other published data are used as inputs for a comparative risk model that estimates the impact of hospitalized quinolone-susceptible and -nonsusceptible salmonellosis cases attributable to freshwater aquaculture.;Results from the research show that quinolone-nonsusceptible salmonellosis causes significantly longer and more costly hospital stays and higher mortality in these two settings. Regulatory practices for aquaculture production practices, including antibiotic use, in Guangdong are currently not effective in ensuring adequate safety of farmed aquatic products. While the health system impact of quinolone-nonsusceptible Salmonella from aquaculture products is relatively small, the impact of antibiotic-resistance in foodborne bacteria pathogens in general may be substantial in terms of hospital stays, hospital costs and mortality. Recommendations for controlling antibiotic use in food production and for conducting further research are offered.