This information is intended for health care professionals.
What is an adverse event following immunization (AEFI)?
An adverse event following immunization is any untoward medical occurrence which follows immunization and which does not necessarily have a causal relationship with the usage of the vaccine. The adverse event may be any unfavourable or unintended sign, abnormal laboratory finding, symptom or disease.
Why is reporting an AEFI important?
Provincial reporting of an AEFI is an important component of the overall safety assessment of any vaccine. Individual case reports of AEFIs represent an important source of data as they have the potential to generate signals of adverse reactions not previously recognized in clinical studies.
Am I required to report AEFI?
Yes, you are required to report AEFI to your local Medical Officer of Health under Section 38 of the Health Protection and Promotion Act (HPPA) and its accompanying regulation, O.Reg 569 s.7.
What types of AEFI should be reported?
Under the HPPA, Section 38 the following events are considered reportable:
- persistent crying or screaming, anaphylaxis or anaphylactic shock occurring within forty-eight hours after the administration of an immunizing agent,
- shock-like collapse, high fever or convulsions occurring within three days after the administration of an immunizing agent,
- arthritis occurring within forty-two days after the administration of an immunizing agent,
- generalized urticaria, residual seizure disorder, encephalopathy, encephalitis or any other significant occurrence occurring within fifteen days after the administration of an immunizing agent, or
- death occurring at any time and following upon an aforementioned symptom
In general, any adverse event following immunization may be reported to your local Public Health for further follow-up and investigation if:
- It has a temporal association with immunization (i.e. the event follows immunization); and
- Has no other clear cause at the time of reporting.
A causal relationship does not need to be proven, and submitting a report does not imply causality.
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.
What happens to the information provided on the Ontario AEFI Reporting Form?
Once a reported AEFI is received by the local health unit, it is reviewed and investigated. The local Medical Officer of Health (MOH) may make recommendations to the vaccine recipient/caregiver with respect to additional follow-up and receipt of further doses of vaccine. Public Health Sudbury & Districts enters AEFI reports into the integrated Public Health Information System (iPHIS), the electronic reporting system for reportable diseases and AEFI in Ontario.
Public Health Ontario (PHO) continuously monitors all AEFI reported via iPHIS and transmits to PHAC for inclusion in the Canadian Adverse Events Following Immunization Surveillance System (CAEFISS), a national database containing AEFIs reported from all provinces and territories in Canada.