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User Guide:
Report of Adverse Events Following Immunization (AEFI)

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Updated: 07 October 2010
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Table of Contents

A. Background

When did National Vaccine Post Marketing Surveillance begin in Canada?

National monitoring of adverse events dates back to 1965 and was the responsibility of the Laboratory Centre for Disease Control (LCDC) for vaccines as well as for drugs. LCDC’s responsibility was limited to human preventive vaccines in 1987. That same year, a computerized database was created to collate adverse event reports from all sources. The Canadian Adverse Event Following Immunization Surveillance System (CAEFISS) is currently overseen by the Vaccine Safety Section in the Surveillance and Outbreak Response Division within the Centre for Immunization and Respiratory Infectious Diseases (CIRID) of the Public Health Agency of Canada (PHAC). 

What is an Adverse Event Following Immunization (AEFI)?

An AEFI is any untoward medical occurrence in a vaccinee which follows immunization and which does not necessarily have a causal relationship with the administration of the vaccine (based on International Conference on Harmonisation (ICH) Topic E6 definition). The adverse event may be any unfavourable and/or unintended sign, abnormal laboratory finding, symptom or disease.

Should all AEFIs be reported?

No. During their development, vaccines undergo rigorous testing for safety and efficacy. During these “pre-licensure trials” efforts are made to capture every single adverse event that follows immunization. By the time a vaccine is authorized for marketing, the safety profile for common adverse events such as inflammation at the injection site or mild fever is well known. It is always important to counsel vaccinees or their guardians regarding the possible occurrence of such reactions, but there is no need to report such expected events unless they are more severe or more frequent than expected.

What type of AEFI should be reported? 

AEFIs should be reported when the event: 

  • Has a temporal association with a vaccine
  • Has no other clear cause at the time of reporting: A causal relationship between immunization and the event that follows does not need to be proven and submitting a report does not imply or establish causality.  Sometimes the vaccinee’s medical history, recent disease, concurrent illness/condition and/or concomitant medication(s) can explain the event(s). 

Of particular interest are those AEFIs which meet one or more of the following criteria:

  • Are of serious nature: A serious adverse event is one that is life threatening or results in death, requires hospitalization or prolongation of an existing hospitalization, results in residual disability or causes congenital malformation.
  • Require urgent medical attention.
  • Are unusual or unexpected: An event that has either not been identified previously or one that has been identified previously but is, at current, being reported at an increased frequency.  For additional information regarding unusual or unexpected events, please refer to the Canadian Immunization Guide which can be accessed on-line at http://www.phac-aspc.gc.ca/publicat/cig-gci/index-eng.php.

If there is any doubt as to whether or not an event should be reported, a conservative approach should be taken and the event should be reported.

Of Note: PHAC collects AEFI reports following the administration of active immunizing agents (vaccines).  In comparison, Health Canada (HC) collects case reports of adverse events following the administration of therapeutic (passive) and diagnostic agents. When an adverse event follows the administration of an active immunizing agent (e.g., vaccine) that is administered simultaneously with a passive immunizing agent (e.g., immune globulin) and/or a diagnostic agent (e.g., tuberculin skin test), complete the AEFI Report form.  Provide the name of the active immunizing agent, in addition to the passive immunizing agent and/or diagnostic agent, in section 4c, and follow the established procedures for reporting an AEFI in your province.  This information will subsequently be forwarded to PHAC and to HC. Alternatively, if no active immunizing agent (vaccine) has been administered, an AEFI Report form should not be completed.  Instead, please follow the established procedures in your province for reporting an adverse drug reaction to HC (e.g., completion of the Canada Vigilance Reporting Form). 

Who reports AEFIs?

AEFI reports originate from multiple sources in Canada. Vaccine manufacturers are required by law (Food and Drugs Act and Regulations) to report to PHAC all serious AEFIs with vaccines for which they are the Market Authorization Holder within 15 days of knowledge of their occurrence. No other legal requirement for reporting AEFIs exists nationally. Several provinces have enacted mandatory AEFI reporting requirements. However, overall, reports are generally submitted on a voluntary basis by vaccine providers and other health care professionals. 

The usual and preferred reporting flow is from local or regional health units to central provincial/territorial immunization programs. Reports are forwarded to PHAC electronically, or in hard copy by the provinces and territories after all personal identifying information has been removed.  On occasion, reports may be submitted directly to PHAC by travel health clinics, pharmacists, physicians or the general public.

To enhance timely detection and assessment of serious adverse events involving children, PHAC funds an active pediatric hospital based surveillance system known as the Immunization Monitoring Program ACTive (IMPACT). AEFI reports completed by the IMPACT nurse monitors are sent to the appropriate provincial/territorial jurisdiction as well as to PHAC directly. Special numbering of the reports is done to avoid duplication.

What is done with AEFI reports at the provincial/territorial level? 

AEFI reports are received at the local/regional level from multiple sources: physicians, nurses, pharmacists, public health, IMPACT, and the public. Recommendations for future immunizations are usually made at the local/regional level. In provinces and territories with electronic systems, the data are entered at the local health unit or regional health authority level and are then shared with the province/territory.  The AEFI data are analyzed and disseminated at the provincial/territorial level to provincial/territorial stakeholders.  Data are then sent electronically to PHAC. Those provinces and territories with paper based systems either fax this information directly to PHAC and/or enter the information in a provincial database.

What is done with AEFI reports at the national level?

Personnel in the Vaccine Safety Section screen all submitted reports, ensure they are entered into the CAEFI database and coded using standard international coding terminology. Reports are monitored with special attention to serious or unusual events that could signal a concern regarding vaccine safety. Canadian data are periodically forwarded on to the World Health Organization (WHO) International Drug Monitoring Program in Uppsala, Sweden, where global data are analyzed for any evidence of safety concerns.

When, why and how was a national AEFI report form first developed?

Critical groundwork for the current CAEFISS system was done at the Post Marketing Surveillance of Vaccine Associated Adverse Events workshop in 1990, sponsored by Health Canada’s Bureau of Communicable Disease (CDWR 1991; Vol. 17-19:97-98) and attended by Federal, Provincial and Territorial stakeholders as well as vaccine manufacturers, key non-governmental organizations and expert scientific advisors. The purpose of the workshop was to develop a framework for a coordinated approach to optimize vaccine post marketing surveillance in Canada. At the workshop, post marketing surveillance for vaccines was defined as the coordinated, structured, systematic, ongoing collection of data and their subsequent epidemiologic analysis and dissemination. It was recommended that passive surveillance be centrally aggregated with input by public health and physicians and supplemented by active surveillance activities.

The first national vaccine adverse event report form was developed through a federal/provincial/territorial collaborative process during the year following the 1990 workshop. It was agreed that the form would list several adverse events considered to be of public health importance. Reporters could check off the specific event and add written detail. There was also an “other” box so that any adverse event of concern to a reporter could be reported.  It was agreed that all Provincial/Territorial AEFI forms would be based on the national form with nothing deleted but items could be added if they were of specific interest to a region.  Case definitions were also developed, although many simply specified that a physician diagnosis would be required. In 1996, the AEFI report form was revised and it is that version which has been in use until now. A series of federal / provincial / territorial workshops held from 2000-2002, led to the development of published functional standards, a minimum core data set and updated data definitions for AEFI reporting (CCDR 2002; 28).

Why has the form been revised?

Priorities to improve vaccine safety surveillance in Canada were established during the development of the National Immunization Strategy (NIS). As a part of the efforts to improve voluntary AEFI reporting, it was decided to revise the AEFI report form. This has been done over the last two years by members of the Vaccine Vigilance Working Group (VVWG) which is a federal/provincial/territorial group that reports to the Canadian Immunization Committee (CIC). Another reason to revise the form was to facilitate application of standardized AEFI case definitions developed by the Brighton Collaboration which is an international voluntary group whose goal is to facilitate the development, evaluation, and dissemination of high quality information about the safety of human vaccines.

How is Privacy and Confidentiality of information ensured?

Personal health information is confidential. All provinces, territories and PHAC take great care to protect personal health information.  Health care workers are encouraged to discuss with clients, or the clients' caregiver, the reason for reporting the AEFI and the confidentiality of all collected information.  For further information regarding the protection of personal health information you may contact the privacy representatives at your local public health office.  Alternatively, the Privacy Act can be accessed online at the following address: http://laws.justice.gc.ca/en/P-21/index.html (External link) External link

Where and when can copies of the AEFI report form be obtained?

The new form will be introduced early in 2009 in most but not all provinces and territories. The form itself, along with information regarding its implementation in Canada, will be published on the Web at http://www.phac-aspc.gc.ca/im/aefi-form_e.html. In addition, the form can be viewed in the Compendium of Pharmaceuticals and Specialties and hard copies can be obtained from local public health units, hospitals, clinics (including travel clinics), etc.

B. Guidelines on how to complete sections of the AEFI form:

This guide is intended to be used when completing the Report of AEFI for submission to provincial and territorial authorities as well as to PHAC. Its purpose is to provide assistance on how to accurately complete the form. It is not intended to guide treatment. Treatment of all AEFIs should proceed, as appropriate, prior to completing the AEFI form. Following the immediate care of the vaccine recipient, the AEFI form can be completed with all available information.  

Given the variation in practice between each of the provinces and territories, sections of the form may not be applicable to all settings. If in doubt, please contact your local public health unit.

Report of Adverse Events Following Immunization (AEFI)

Complete each section of the AEFI form as follows:

On the top right hand corner: Indicate whether the AEFI report being submitted is an “Initial” or a “Follow up” report. For all “Follow up” reports, provide the “Unique episode number” and/or “Region #” of the initial report.