These can last a few hours to a few days after vaccination. This is the body's natural response, as it's working hard to build protection against the disease. Learn more about: COVID-19 vaccine safety and side effects: Common side effects....

After a vaccine is authorized for use in Canada, we monitor its safety and effectiveness (how well it works) in people. This monitoring system is called post-market surveillance. During the COVID-19 pandemic, we're increasing: our monitoring and assessment activities of emerging safety issues....

COVID-19 vaccines have been shown to be very effective at preventing severe disease, including hospitalization and death due to COVID-19....