Are there long-term side effects caused by mRNA COVID-19 vaccines?
The medical and scientific community is confident in the long-term safety of the mRNA COVID-19 vaccines for several reasons:
- The history of vaccines shows that delayed effects after vaccination can happen. But when they do, these effects tend to happen within six weeks of receiving a vaccine. This is why regulators in Canada and many other countries require at least eight weeks of safety data before approving a vaccine.
- The mRNA vaccines have been in development for many years and have been studied before for flu, Zika, rabies, and cytomegalovirus (CMV). In addition, cancer research has used mRNA to trigger the immune system to target specific cancer cells. Decades of studying mRNA vaccines have shown no long-term side effects.
- Canada’s vaccine safety system has proven time and again that the data necessary to get through the approval process is sufficient to prove safety, even for the long term. The data and safety tests for the mRNA vaccines met the same standards as other vaccines that have been approved in Canada.
Date last reviewed:
Thursday, Nov 18, 2021