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- Declaring the outbreak over
- Outbreak wrap-up activities
- Outbreak debriefs
- Knowledge translation
- Long term implications
Post-outbreak activities take place once the outbreak investigation is complete. Whether or not the source of the outbreak was identified, outbreak investigations eventually come to a close. All members of the investigative team should regularly analyze and assess all available evidence describing the progression of the outbreak in order to determine when to declare the outbreak over and conclude coordinated response efforts. In addition to deciding that the outbreak is over, there are many wrap-up activities that should take place including preparing a final epidemiological summary, communicating to affected public health partners, and sharing the findings of the outbreak through knowledge translation activities and applications such as Outbreak Summaries. A structured review of the outbreak with the outbreak team should take place in the form of a debrief session to address practices that worked well and to identify recommendations and follow-up actions to improve future outbreak response. For some outbreaks, there may be long term implications such as public inquiries, changes to practices and policy, and further reviews and studies.
Declaring the outbreak over
Declaring the end of an enteric illness outbreak is a key step in the investigation process. It is an important component of assessing and communicating risk to the public and informs decisions to demobilize outbreak resources and remove temporary restrictions that may have been instituted to mitigate risk.
Enteric illness investigators from Canada, the European Union (EU) and the United States have developed criteria for investigators at all levels of government to facilitate a science-based approach to declaring the end of enteric (bacterial, viral and parasitic) illness outbreaks in community settings where disease transmission is predominately foodborne, waterborne, or zoonotic. Three criteria were developed to guide the decision to declare the end of an enteric illness outbreak: determining that illnesses have returned to baseline levels (criterion 1), identifying the last time that individuals may have been exposed to the outbreak source (criterion 2), and allowing enough time to pass to allow these individuals to become ill and be reported to public health authorities (criterion 3).
Declaring the outbreak over examples:
- Case study, Exercise 6: Declaring the outbreak over
- Case study, Module 4: Declaring the outbreak over
Outbreak wrap-up activities
All members of the investigative team should regularly analyze and assess all available evidence describing the progression of the outbreak in order to determine when coordinated response efforts should be concluded. There are several wrap-up activities that should take place following the end of an outbreak investigation.
Final Epidemiological Summary
The final epidemiological summary will have similar content and layout to epi summaries prepared during the course of an outbreak investigation. The final epi summary often serves as the official record of the outbreak investigation and tends to be longer, with more background and context than typical epi summaries, and should include overall investigative conclusions and recommendations for future outbreaks. Final epi summaries typically require additional approvals, especially if circulated beyond the investigative team. The lead epidemiological partner is usually responsible for creating the first draft of the epi summary, which is written collaboratively with food safety and laboratory partners.
Following an outbreak, adding the outbreak findings and description to the Outbreak Summaries application will ensure that key information is captured in a systematic way. Outbreak Summaries is a secure, web-based application on the Canadian Network for Public Health Intelligence (CNPHI) that provides a platform for local/regional, provincial and federal public health professionals to report standardized data from enteric illness outbreak investigations conducted in their respective jurisdictions. The application allows users to monitor trends in outbreaks and provides information for use in hypothesis generation, policy development, program evaluation, and public health planning.
Investigative partners should share the decision to declare the outbreak over and deactivate coordinated investigative activities with their respective jurisdictions. Public health partners who were notified of the outbreak investigation for case finding purposes should also be notified when the investigation is over. If partners were asked to interview cases using a specific questionnaire or run additional laboratory tests for specific pathogens, they should also be notified that these actions are no longer required. This can be achieved through a Public Health Alert. If possible, share the source of the outbreak and a copy of the final epi summary. If the public was notified of the outbreak investigation, they should also be notified of the outcome of the investigation.
Outbreak wrap-up examples:
- Case study, Module 4: Closing the investigation – OICC deactivation
- Case study, Module 4: Documenting the outbreak – Chronologies
- Case study, Module 4: Documenting the outbreak – Final epi summary
- Case study, Module 4: Documenting the outbreak – Outbreak summaries
A post-outbreak review may be conducted at the request of any of the investigative partners. These reviews, or debriefs, are typically chaired by a member of the lead organization who was not involved in the outbreak response. In some cases, an expert from a jurisdiction not implicated in the investigation could be invited to chair the call. The overall objective of the debrief meeting is to discuss the outbreak investigation and to identify processes that worked well and areas for improvement. Where possible, specific recommendations and action items to improve future investigations should be recorded and a person or organization should be responsible for following up on the progress of the debrief recommendations. Ideally, the outbreak debrief should take place as soon as possible after the conclusion of the outbreak.
Knowledge translation (KT) refers to the activities involved in moving knowledge into practical use. This is an iterative process that includes synthesis, dissemination, exchange and application (Government of Canada, 2014).
A KT product or activity is created to actively and effectively share useful knowledge with an end-user or audience. The “end user” might be a medical practitioner, a nurse, a teacher, a school administrator, a legislator, an epidemiologist, a community health worker, a policy analyst or, even more simply, a parent. KT is a spectrum of activities which change according to the type of research, timeframe, and the audience being targeted. Some examples of KT activities are: presentations at a conference, final report summaries, educational meetings or workshops, press releases, website pages, and webinars.
There is always a need to improve linkages between the creation of knowledge and informed decisions in policy and practice. In a public health context, KT provides an opportunity to take what we know, give it value, and put it to use to address public health issues.
Knowledge translation examples:
- Case study, Module 4: Knowledge translation
- PHAC Salmonella and reptiles handout
- PHAC Healthy Animals, Healthy People Poster
- Foodborne Illness in Ontario — Infographic. Ontario Agency for Health Protection and Promotion (Public Health Ontario). 2014. Ontario health profile infographics. Toronto, ON: Queen’s Printer for Ontario.
- Prevention from the Farm to the Table: Lessons learned from Salmonella outbreaks (Infographic) (see page 3). 2010. Centers for Disease Control and Prevention.
Long term implications
For some outbreaks, especially those that have attracted the attention of the media, a debrief with investigative partners is not enough. Following an outbreak, a public inquiry may be initiated. An inquiry is an official review of events and actions by an external reviewer. The main product of the inquiry is a public report which summarizes the issues and gives recommendations for improving similar situations in the future. Example reports can be found below.
- O’Connor DR. 2002. Report of the Walkterton Inquiry: The Events of May 2000 and Related Issues. Toronto, Ontario, Canada. http://www.archives.gov.on.ca/en/e_records/walkerton/
- Liang RD. 2002. Report of the Commission of Inquiry into matters relating to the safety of the public drinking water in the City of North Battleford, Saskatchewan. http://www.publications.gov.sk.ca/details.cfm?p=9111
- Weatherill S. 2009. Report of the Independent Investigator into the 2008 Listeriosis Outbreak. Catalogue number: A22-508/2009E-PDF. http://publications.gc.ca/site/eng/361474/publication.html
- Government of Canada. Action on Weatherill Report Recommendations to Strengthen the Food Safety System: Final Report to Canadians. Catalogue Number: A22-551/2011E-PDF. ISBN: 978-1-100-19665-7. http://publications.gc.ca/site/eng/408918/publication.html
- Health Canada. Learning from SARS: Renewal of public health in Canada – Report of the National Advisory Committee on SARS and Public Health. Catalogue Number: H21-220/2003E. ISBN: 0-662-34984-9. https://www.canada.ca/en/public-health/services/reports-publications/learning-sars-renewal-public-health-canada.html
Changes to procedures and policies
Outbreak investigations may result in changes to procedures and practices. One example of a change in practice following an outbreak investigation is the Enhanced National Listeriosis Surveillance Program, which was initiated following a listeriosis outbreak in 2008. This outbreak also resulted in changes to routine laboratory practice through the implementation of PFGE sub-typing of listeria isolates at the provincial level.
Outbreak investigations can also result in policy changes. Health Canada works with government, industry and consumers to establish policies, regulations, and standards related to the safety of food sold in Canada. Examples of Health Canada policy and guidance documents that were created as a result of outbreak investigations are below.
Guidance documents and policy examples:
- Health Canada. 2014. Guidance on Mandatory Labelling for Mechanically Tenderized Beef. http://www.hc-sc.gc.ca/fn-an/legislation/guide-ld/mech-tenderized-beef-boeuf-attendris-meca-eng.php
- Health Canada. 2011. Policy of Listeria monocytogenes in Ready-to-Eat Foods. http://www.hc-sc.gc.ca/fn-an/legislation/pol/policy_listeria_monocytogenes_2011-eng.php
- Federal/Provincial/Territorial (FPT) Donair Working Group. 2008. Management of the Risks Related to Consumption of Donairs and Similar Products (Gyros, Kebabs, Chawarmas and Shawarmas). http://www.hc-sc.gc.ca/fn-an/legislation/guide-ld/manage_ris_donair-eng.php
- Health Canada. 2006. Policy on Managing Health Risk Associated with the Consumption of Sprouted Seeds and Beans. http://www.hc-sc.gc.ca/fn-an/legislation/pol/sprouts_pol_pousses-eng.php
- Health Canada. 2000. Managing Health Risk Associated with the Consumption of Unpasteurized Fruit Juice/Cider Products. http://www.hc-sc.gc.ca/fn-an/legislation/pol/rev_unpast_juice_policy-rev_politique_jus_non_past_14-09-2000-eng.php
Research and studies
At the conclusion of an outbreak investigation, there are often many unanswered questions remaining. These questions may be addressed through research studies that can continue beyond the timelines and scope of the original outbreak investigation. Further studies are especially important if the outbreak involved a new or unusual pathogen. Economic evaluations are another common type of post-outbreak study that assess the cost-effectiveness of outbreak investigations and food safety measures.
- This Microsoft Word document provides a suggested template for the content and layout for communicating proposals to deactivate the coordination committee and declare the outbreak over.
- This Microsoft Word document provides a suggested template for the content and layout of an epidemiological summary.
- This Microsoft Word document provides a suggested template for the content and layout of an outbreak investigation report or final epidemiological summary.
- This PDF document provides an overview of the Outbreak Summaries application, its key features and benefits, and an example of how it can be used during an outbreak investigation.
- This Microsoft Word document provides instructions and suggested formatting for creating chronologies for outbreak investigations.
- This Microsoft PowerPoint document provides formatting instructions for creating a visual timeline of events in an outbreak investigation, which documents cases over time, as well as key events, and public health actions.
- This Microsoft Word document can be used as a template for a typical coordination committee debrief teleconference.
- This resource contains a list of Canadian and International conferences of interest to public health professionals working in enteric outbreak response.
- This template developed by Dr. Melanie Barwick at the Hospital for Sick Children provides a series of steps and checklists to consider when creating a KT plan such as identifying partners and users, strategies, evaluation, and implementation. Barwick, M. (2008, 2013). Knowledge Translation Planning Template. Ontario: The Hospital for Sick Children.
- The National Collaborating Centre for Methods and Tools (NCCMT) is one of six National Collaborating Centres for Public Health in Canada. This Registry’s inventory of methods and tools supports the planning, doing and evaluating of public health policies and practices across all four types of knowledge translation activities.
Government of Canada, Canadian Institutes of Health Research, Knowledge Translation. “About Knowledge Translation”. Retrieved 2014-12-04. Available at: http://www.cihr-irsc.gc.ca/e/29418.html
World Health Organization. 2008. Foodborne disease outbreaks: guidelines for investigation and control. WHO Press, World Health Organization, Geneva, Switzerland. http://www.who.int/foodsafety/publications/foodborne_disease/outbreak_guidelines.pdf