Common side effects following administration of the AstraZeneca vaccine are typically mild or moderate and are common of many vaccines (external link), including:
- pain at the site of injection
- body chills
- feeling tired
- feeling feverish
These are common side effects of vaccines and do not pose a risk to health. As with all vaccines, there’s a chance that there will be a serious side effect, but these are rare. A serious side effect might be something like an allergic reaction.
On May 11, the Province announced it would be pausing the rollout and administration of first doses of the AstraZeneca COVID-19 vaccine (external link). The decision was made out of an abundance of caution and due to the increasing reports of the rare blood clotting condition, known as vaccine-induced immune thrombotic thrombocytopenia (VITT), linked to the AstraZeneca vaccine.
Individuals should seek medical attention if they develop the following symptoms four or more days after receiving the AstraZeneca COVID-19 vaccine:
- shortness of breath
- chest pain
- leg swelling
- persistent abdominal (belly) pain
- neurological symptoms (such as sudden onset of severe or persistent worsening headaches or blurred vision)
- skin bruising or tiny blood spots under the skin beyond the site of the injection
If you experienced rare blood clots with unusual platelets following your first dose of the AstraZeneca COVID-19 vaccine, it is not recommended that you receive a second dose of any version of the AstraZeneca vaccine.
On May 21, 2021, the Province announced that second dose administration of the AstraZeneca COVID-19 vaccine will continue (external link). For a limited time during the week of May 24, individuals who received their first dose of AstraZeneca during the period of March 10, 2021 to March 19, 2021 may opt for an earlier dose interval of 10 weeks with informed consent. Halton Region Public Health did not offer the AstraZeneca vaccine during this time period. If you received the AstraZeneca vaccine during this time period outside of Halton, please contact the pharmacy or primary care office where you received your first dose to arrange your second dose appointment.
Individuals may choose to have a second dose of AstraZeneca COVID-19 vaccine, or wait to determine which vaccine they may receive at a later date when more data is available on mixed vaccine series (for example, having a first dose of AstraZeneca and a second dose of one of the mRNA vaccines). It is very important that people receive both doses to complete their vaccine series.
If individuals choose to receive AstraZeneca COVID-19 vaccine as their second dose, an interval of 12 weeks or more provides good protection. Individuals should be informed of the risks and benefits of their vaccine choices. The reported risk of VITT after the second dose of AstraZeneca COVID-19 vaccine is much lower than observed after the first dose.
For more information on the safety of the AstraZeneca vaccine, please read Health Canada’s website (external link).