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Canadian Adverse Events Following Immunization Surveillance System (CAEFISS)

The Canadian Adverse Events Following Immunization Surveillance System, or CAEFISS is a federal/provincial/territorial public health post-market vaccine safety monitoring system. CAEFISS has the following objectives:

  1. to continuously monitor the safety of marketed vaccines in Canada;
  2. to identify increases in the frequency or severity of previously identified vaccine-related reactions;
  3. to identify previously unknown adverse events following immunization(AEFI) that could possibly be related to vaccine (unexpected AEFI);
  4. to identify areas that require further investigation and/or research; and
  5. to provide timely information on AEFI reporting profiles for vaccines marketed in Canada that can help inform immunization related decisions.

Public Health Reporting Pathway for Adverse Events Following Immunization (AEFIs) to CAEFISS

The diagram below depicts how AEFI reports flow from origin (vaccine recipient) to the Agency. CAEFISS includes spontaneous, enhanced and active AEFI reporting processes that are further described below. Over 90% of CAEFISS reports are submitted by public health authorities in the provinces and territories, who in turn receive them from local public health units.  Provincial and territorial authorities also receive reports from federal authorities that provide immunization within their jurisdiction (including First Nations and Inuit Health Branch, Correctional Services Canada and Royal Canadian Mounted Police). Most of these reports are generated by nurses, physicians or pharmacists who provide immunizations or who care for individuals with AEFIs. AEFIs received by National Defence and the Canadian Armed Forces are reported directly to the Agency. On rare occasions, AEFI reports are submitted to the Agency directly from physicians, pharmacists, travel clinics and the public.

Market Authorization Holders (MAHs) (i.e. pharmaceutical industry) report serious as well as all unexpected (serious and non-serious) adverse events directly to Health Canada; some MAHs also send reports to the Agency on a voluntary basis. MAH reporting reports less than 5% of all reports received.

Canada also has an active paediatric hospital-based surveillance network for selected serious AEFIs, including but not limited to febrile seizures, other neurologic adverse events, thrombocytopenia, severe vaccination site reactions and intussusception. Known as IMPACT (Immunization Monitoring Program ACTive), the network includes 12 paediatric hospitals across Canada which together represent over 90% of all paediatric tertiary care admissions in the country. At each IMPACT centre, a nurse monitor uses several methods to identify admissions to hospital for the specified adverse events and determines whether or not the events followed immunization and thus should be reported. Each IMPACT centre reports directly to the Agency ensuring timely identification of serious adverse events, and the same report is also sent to public health at the provincial/territorial or local public health unit level depending on standard practice for a given jurisdiction. As each report has a unique IMPACT identification number, it is only entered once into CAEFISS.

Figure 1: Public Health Reporting Pathway for Adverse Events Following Immunization (AEFIs) to CAEFISS

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Enlarge Figure 1

The flow of AEFI reports as shown in the diagram enable specific actions to be taken at each step along the way.

  • AEFI management, including investigation as appropriate to determine possible cause, is usually undertaken by the reporting immunization or healthcare provider.
  • Individual public health action, such as advice regarding future immunizations, is taken at the Public Health Unit or immunization provider level.
  • Federal/provincial/territorial health authorities collect AEFI reports as part of ongoing evaluation of their immunization programs. At the population level, public health action related to AEFI reports could include changes in immunization program policy.
  • The Agency collates AEFI reports in the Canadian Adverse Event Following Immunization (CAEFI) database for purposes of signal detection analysis and reporting.
  • The Agency shares AEFI data with Health CanadaExternal Link to enable regulatory action related to vaccines marketed in Canada.

CAEFISS Data Reports and Publications

CAEFISS Quarterly Reports

Previously Published Vaccine Safety Reports

AEFI summaries for vaccines administered over specific time periods

  • Canadian National Report on Immunization: Chapter 5-Vaccine Safety: Surveillance of Adverse Events Following Immunization. (with trends from 1992 to 2004) (archived)
  • 1998 National Report (interim) on Immunization Vaccine Safety Issues and Surveillance (1998 reports plus trends from 1993-1997). In Journal of the Canadian Paediatric Society July/August 1999 Vol. 4:SupplC
  • Canadian Report on Immunization: Update on Vaccine Safety Issues and Surveillance In Journal of the Canadian Paediatric Society 1998 Mar/Apr Vol. 3:SupplB
  • Canadian National Report on Immunization 1996: Surveillance of Adverse events temporally associated with vaccine administration (archived)  CCDR 1997 Vol. 23S4External Link
  • Adverse events temporally associated with vaccines – 1992 report. (archived) CCDR 1995 Vol. 21-13:117-128. (PDF document)External Link
  • Adverse events temporally associated with vaccines – 1991 report. CCDR 1993; 19:168-78 (not available online)
  • Adverse events temporally associated with vaccines – 1990 report. Can Fam Physician 1993; 39:1907-13.

Reports on specific vaccines

  • Serious adverse events associated with Bacille Calmette-Guérin vaccine in Canada. Pediatric Infectious Disease Journal 2005; 24:538-541.
  • Influenza vaccine-associated adverse events: Results of passive surveillance, Canada 2001-2002. (archived) CCDR Dec 2002; Vol 28-23:189-196External Link
  • Review of adverse events reported following use of yellow fever vaccine – Canada, 1987-2000. (archived) CCDR Jan 2002; Vol 28-2:9-15External Link.

Reports on specific adverse events

  • Oculo-respiratory syndrome following influenza vaccination: Review of post-marketing surveillance through four influenza seasons in Canada. (archived) CCDR 2005; Vol. 31-21:217-225External Link Oculo-respiratory syndrome in association with the influenza vaccine: Canada, October-November 2000 (Preliminary report) (archived) CCDR 2000; Vol. 26-23:201.External Link

IMPACT Vaccine Safety Publications (PDF document)External Link

For an electronic copy of these reports, please contact: