Appendix B: Evaluation of food-borne enteric illness prevention, detection and response activities at the Public Health Agency – 2011 Germany E. coli O104:H4 outbreak

Appendix B: Lessons Learned from the 2011 Germany E. coli O104:H4 outbreak


On May 19, 2011, Germany’s Robert Koch Institute (Germany’s national public health organization) received its first notification of a cluster of hemolytic uremic syndrome (HUS) cases. HUS is a sign of serious illness, usually caused by a toxin-producing infection and it often leads to kidney damage. The outbreak was quickly confirmed and by May 21, 2011, Germany reported an ongoing, severe outbreak of a Shiga-toxin producing Escherichia coli bacteria, later identified as serotype O104:H4.

By July 26, 2011, when the Robert Koch Institute declared the outbreak to be over, 908 HUS cases (34 deaths), and 3,167 non-HUS EHEC cases (16 deaths) were reported internationally (see World Health Organization table below). In total, 4,075 people became ill and 50 died during this outbreak. 

This outbreak was unique amongst recent food-borne outbreaks in several respects.  Adult women were particularly at risk and there was a markedly higher than expected proportion of HUS cases (approximately 22 per cent compared to an expected rate of less than 10 per cent). Patient outcomes were also worse than expected, including a marked increase in severe neurological complications and numerous deaths linked to HUS and non-HUS infection. Finally, the scope and speed of the outbreak alarmed the public and many public health organizations.


The outbreak strain was identified as a Shiga-toxin–producing E. coli strain
O104:H4. This rare and unanticipated strain has the ability to produce a severe toxin, as well as adhere to the intestines, which explains the severity of illness seen in many cases.

There was an initial delay in the detection of the pathogen responsible for the outbreak — almost a week had been reported from the initial confirmation of the illness to reports being received by the Robert Koch Institute. This falls in line with the agreed timelines for reporting outbreaks in Germany at the time (and included mail as a means of transmitting information):

  • doctors must notify local health agencies of reportable infections within 24 hours
  • local health agency then has until the third working day of the following week to report these to state authorities
  • state authorities have an additional week to inform national authorities (this process was accelerated to a day during this outbreak).Footnote 98

Some have stated that the lack of centralization impeded the sharing of information from public health laboratories to federal organizations.Footnote 99 At the time of the outbreak, there was no centralized electronic system that allowed for real-time exchange of information on human illness between all local public health laboratories and federal laboratories.

Investigations (epidemiological and laboratory)

After laboratory characterization of the pathogen, investigations were rapid and extensive, supported by international collaboration. Within a week from the start of the laboratory investigation, screening tools and a novel method for detection of the pathogen in clinical and food specimens were developed, tested, and shared with national and international networks.

The impact of this food-borne outbreak was equally swift and significant. The outbreak required extensive and collaborative efforts from local, regional, national, and international health organizations. It is estimated that over 100 epidemiologists were required by the Robert Koch Institute alone to investigate the outbreak. 

Identifying the outbreak source was challenging and involved several epidemiologic studies, combined with traceback investigation. This highlighted the importance of public health and regulatory food safety partners working together in the investigation. The epidemiologic methods included case interviews, three case-control studies, and a restaurant cohort study.


Communicating to the public is a challenge for all public health organizations in the midst of an outbreak. The speed and scope of this outbreak typified the challenge, as the Robert Koch Institute sought to provide sufficient information to inform and protect the public, in the midst of uncertainty about the cause of the outbreak. 

Early mistaken attribution was a problem.Footnote 100 Initially, the public were cautioned about consumption of tomatoes, cucumbers and lettuce. Subsequently, Spanish cucumbers were falsely identified, before the public was warned about consuming vegetables in general. Finally, sprouts and germ buds were explicitly added to the warning as the investigation closed in on the source, before conclusively determining that raw sprouts had caused this outbreak.

The Public Health Agency: comparisons


The German public health system is similar to Canada, in that it relies upon collaboration between local, state and national levels. After the 2008 Listeriosis outbreak and the determination in Canada that roles and responsibilities needed clarification, the guiding food-borne outbreak protocol was strengthened and a federal emergency response plan was developed. Regular updating, training, and testing are standard. These protocols and plans provide a strong framework for Canadian food-borne outbreak response, which is an asset that Germany could have benefited from. 

Beyond this formal framework, Canada also benefits from traditionally strong relations between the Public Health Agency and its provincial/territorial public health partners. Partly due to forced post-war decentralization, the Robert Koch Institute and German state public health organizations lack such close relations. This impacted the effectiveness and efficiency of information sharing and coordinated response.Footnote 101


The detection of all pathogens, including unexpected ones such as E. coli O104, is facilitated in Canada by the Canadian Network for Public Health Intelligence and PulseNet platforms. Rapid detection and real-time information sharing across Canadian laboratories (both provincial and federal levels) through PulseNet enables the Canadian system to rapidly detect food-borne threats, share information, and assess situations. The Public Health Agency has also made significant progress in improving laboratory capacity amongst its provincial counterparts, through training and technology transfer. With a stronger, well connected laboratory system, Canada is better positioned then Germany, or than before the 2008 Listeriosis outbreak, for rapid detection and timely response.

Epidemiological Capacity

The Germany outbreak created a sudden, massive demand for epidemiological resources within the Robert Koch Institute to conduct the outbreak investigation. Although the Public Health Agency employs a wide array of epidemiologists amongst its many public health programs, it would be similarly challenged to swiftly deploy sufficient numbers of epidemiologists trained and experienced in food-borne illness. 


In the Germany outbreak, communication challenges arose which are common to all countries and all types of outbreaks. It is always difficult to satisfy public demands for information and deliver a cohesive and coordinated message amongst partners, in the midst of confusion, ongoing investigation, and competing sources of information vying for the public’s attention. Despite these challenges, the Public Health Agency is well positioned to communicate effectively with the Canadian public during a food-borne outbreak. After the 2008 Listeriosis outbreak, a Food Safety Communications Protocol and a Strategic Risk Communications Plan were developed (these were shared with Germany at their request after the E. coli strain O104:H4 outbreak). These tools provide guidance to the Public Health Agency and federal partners on respective roles and responsibilities, as well as guidance amongst potential outbreak scenarios. The risk communications plan provides the Public Health Agency with approaches that can be adapted to various outbreak scenarios.

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