Epidemiology and Infection

Gastrointestinal infection and food poisoning

Source attribution of human salmonellosis using a meta-analysis of case-control studies of sporadic infections

A. R. DOMINGUESa1 c1, S. M. PIRESa1, T. HALASAa2 and T. HALDa1

a1 National Food Institute, Technical University of Denmark, Søborg, Denmark

a2 National Veterinary Institute, Technical University of Denmark, Copenhagen, Denmark


Salmonella is an important cause of human illness. Disease is frequently associated with foodborne transmission, but other routes of exposure are recognized. Identifying sources of disease is essential for prioritizing public health interventions. Numerous case-control studies of sporadic salmonellosis have been published, often using different methodologies and settings. Systematic reviews consist of a formal process for literature review focused on a research question. With the objective of identifying the most important risk factors for salmonellosis, we performed a systematic review of case-control studies and a meta-analysis of obtained results. Thirty-five Salmonella case-control studies were identified. In the meta-analysis, heterogeneity between studies and possible sources of bias were investigated, and pooled odds ratios estimated. Results suggested that travel, predisposing factors, eating raw eggs, and eating in restaurants were the most important risk factors for salmonellosis. Sub-analyses by serotype were performed when enough studies were available.

(Accepted October 18 2011)

(Online publication December 08 2011)