Lessons Learned from Epidemiological Investigations of the Enterohemorrhagic Escherichia coli O104:H4 Outbreak in Germany 2011

Shu-Wan Jian1*, Ding-Ping Liu1, Chi-Tai Fang2,3

2015 Vol.31 NO.11

Correspondence Author: Shu-Wan Jian

  • 1.Epidemic Intelligence Center, Centers for Disease Control, Ministry of Health and Welfare, Taiwan
  • 2.Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University
  • 3.Department of Internal Medicine, National Taiwan University Hospital


In recent years, nationwide and international foodborne outbreakshave become more commonly recognized. When foodborne illness happens, public health officials investigate outbreaks, ensure thescale of diagnostic capability in laboratories for foodborne microorganisms,control it and prevent similar outbreaks from happening in the future. A largeoutbreak of the hemolytic-uremic syndrome associated with enterohemorrhagic Escherichia coli O104:H4 occurred in Germany that ultimately involved more than4,000 persons in 16 countries. We undertook a literature searchrefers to the epidemiological studies of this outbreak, and discussed themethods and results of the main investigations. Early in the epidemiological studies, the team of epidemiological specialists started with initialexploratory interviews and case-control studies which linked to consumption ofraw tomato, cucumber, and salad in northern Germany. Additional recipe-basedrestaurant cohort studies, online questionnaires, trace-back and trace-forward investigations identified sprouts produced by an organic grower in Lower Saxonyas vehicle of transmission. A thorough understanding of the advantages andlimitations of epidemiological studies and typing methods during outbreak investigations is of crucialimportance for selecting the appropriate approaches to explicitly defineoutbreak strains. Recall bias with regard to sprout consumption and potentialselection bias in case-control studies also need to be taken into account to avoid impacts and losses from misidentification of incriminated food.

Keywords:Sprouts;food poisoning;Germany;hemolytic uremic syndrome;foodborne diseases