Side effects of immunization are mostly mild, such as a sore arm or mild fever for a day. However, there is no way to absolutely predict how a specific individual may react to a particular vaccine. If a more serious reaction (adverse event) is suspected, this should be reported to a health care provider or public health office where the vaccine was given.
Procedures and forms to report an adverse event following immunization can be found on the Public Health Agency of Canada’s Vaccine Safety website (external link).
- Canadian Adverse Events Following Immunization Surveillance System (CAEFISS) (external link)
- IMPACT – Canadian Immunization Monitoring Program ACTive: Canadian Paediatric Society (external link)
- World Health Organization: Vaccine Safety (external link)
Public Health Agency of Canada. Canadian Immunization Guide. Evergreen edition. (external link)