Reporting Adverse Events Following Immunization (AEFIs)
When a patient, resident or health care worker experiences or observes an adverse event following vaccination, immunizing staff and physicians have a legal obligation as per The Public Health Act, 1994 to report the event to the medical health officer within a certain time frame, depending on the severity of the event. COVID-19 vaccine related AEFIs can be reported by calling HealthLine 811. If you were immunized by a pharmacist report your AEFI to the pharmacist.
AEFIs are reported in order to:
- continuously monitor the safety of marketed vaccines in Canada;
- identify increases in the frequency or severity of previously identified vaccine-related reactions;
- identify previously unknown AEFIs that could possibly be related to a vaccine;
- identify areas that require further investigation and/or research; and
- provide timely information on AEFI reporting profiles for vaccines marketed in Canada that can help inform immunization-related decisions.
Adverse Events Following Immunization Questions and Answers
What is an Adverse Event Following Immunization (AEFI)?
An AEFI is any untoward medical occurrence that follows immunization but that does not necessarily have a causal relationship with the administration of the vaccine. Specific criteria must be met to define the events as true adverse events, and there must be no coexisting condition that could explain the reaction that occurs.
What are potential reactions from the COVID-19 immunization?
Symptoms are categorized as either local, systemic, neurological or other reactions.
Local reactions are related to injection site pain, swelling, or redness whereas systemic reactions are usually non-specific and can include tiredness, headache, muscle pain, joint pain, chills or fever. Enlarged lymph nodes (swollen glands) that last for several days may also occur. Other reactions may include thrombosis or thrombocytopenia (i.e. blood clots or low platelet count).
The severity of a local or systemic reaction can vary. Mild reactions can be "expected" and do not require reporting. Unexpected and/or serious reactions must be reported, and an assessment and recommendation by a medical health officer must take place prior to providing further immunizations.
A serious AEFI is one that results in hospitalization or a prolongation of an existing hospitalization, or permanent disability/incapacity, is life threatening or results in death.
Serious side-effects after receiving the vaccine are rare. However, should you develop any serious symptoms or symptoms that could be an allergic reaction, call 9-1-1 right away. Symptoms of an allergic reaction include:
- Hives (bumps on the skin that are often very itchy)
- Swelling of the face, tongue or throat
- Difficulty breathing
If you have any concerns about the symptoms you develop after receiving the vaccine, call 811. If you received your vaccine from a pharmacist, please consult them first when possible.
What happens when an AEFI is reported?
When an AEFI is reported Public Health may follow-up with you to collect more information and complete an AEFI report form, if appropriate, which will then be sent to the local medical health officer (MHO). The MHO reviews the report and if there is any recommended follow up, you will be contacted with those recommendations.
On both a provincial and national level these reports are anonymized and then reviewed to identify any unusual concerns. These reports are vital to ensure the safety of all vaccination programs in Canada.