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COVID-19VACCINES—SAFETY & SIDE EFFECTS



Everyone living in Canada will have access to free, safe & effective COVID-19 vaccines, as health authorities have recently announced. Before getting vaccinated, it is important to be aware the safety & side effects of COVID-19vaccines you receive. Vaccines go through extensive trials before they can be introduced in a country. Vaccines are thoroughly tested for safety before they are approved. Same goes true for Covid-19 vaccine too. Vaccines on the market in Canada and other nations are monitored continuously. Commonly reported side effects of vaccination, such as pain at the site of injection, body chills or feeling tired or feverish, are not considered safety concerns to the health of people. Expert doctors and scientists follow strict international standards while deciding whether to approve a vaccine. Like all medicines, vaccines may cause side effects that are usually minor and temporary. More serious side effects are very rare. As experts opine a person is far more likely to be seriously harmed by a disease than by its vaccine.


Vaccine safety


Safe and reliable vaccines can help protect the people from COVID-19. Vaccination is expected to be an effective way to prevent the spread and reduce the impact of COVID-19. The effectiveness and immune response of the vaccine is being monitored as the vaccine is rolled out. COVID 19 vaccine will be an important tool to help stop the spread of the virus and allow individuals, families and workers to safely resume normal life, as the health authorities pronounce. The coronavirus (COVID-19) vaccine does not cause a coronavirus infection. It helps to build up body immunity to the virus, so that the body will fight it off more easily if infection occurs.

After independent and thorough scientific reviews for safety, efficacy and quality, Health Canada has approved four vaccines for use in Canada:

  • Pfizer-BioNTech – approved on December 9, 2020

  • Moderna – approved on December 23, 2020

  • AstraZeneca – approved on February 26, 2021

  • Janssen (Johnson & Johnson) – approved on March 5, 2021

Understanding how COVID-19covid 19 vaccines are approved, how they work and possible side effects is important.


Only vaccines that Health Canada determines to be safe and effective will be approved for use in Canada and available in Ontario. After independent and thorough scientific reviews for safety, efficacy and quality, Health Canada has approved four vaccines for use in Canada that have expected efficacy as follows:

  • Pfizer-BioNTech – expected to be 95% effective after two doses

  • Moderna – expected to be 94% effective after two doses

  • AstraZeneca (AstraZeneca and COVISHIELD) – expected to be 64% effective after two doses

  • Janssen (Johnson & Johnson) – expected to be 66% effective after one dose

The vaccines:

  • were tested on a large number of people through extensive clinical trials

  • have met all the requirements for approval, including safety

  • are monitored for any adverse reactions that may occur after vaccination and appropriate measures will be taken

The vaccines cannot cause COVID-19


This is because they do not contain the SARS-CoV-2 virus responsible for the disease. However, if a person come in contact with the virus just before or after they complete the vaccine series of two doses, they could still develop COVID-19.


Commonly observed side effects with different vaccinations


A mild local reaction resolving by itself within a few minutes is not indicative of an allergic reaction and does not require special observation or specialized assessment prior to subsequent vaccination.