Who has received the AstraZeneca vaccine?
In this province, the AstraZeneca/COVISHIELD vaccine was provided to over 20,000 individuals.
Newfoundland and Labrador has enough mRNA (Pfizer/Moderna) vaccine to immunize individuals ages 12 years and older.
https://www.gov.nl.ca/covid-19/vaccine/gettheshot/
Should I be worried if I have received the AstraZeneca Vaccine?
Health Canada has stated that the AstraZeneca/COVIDSHIELD COVID-19 vaccine continues to be safe and effective at protecting Canadians against COVID-19 and encourages people to get immunized with any of the COVID-19 vaccines that are authorized in Canada.
There have been rare reports of blood clots (Vaccine Induced Thrombotic Thrombocytopenia or VITT) following vaccination with AstraZeneca in Canada and elsewhere in the world. It is not known if blood clots are more common in people who have had blood clots before, people with a family history of blood clots, people with a low platelets, or pregnant women, because VITT does not develop through the same process as usual types of bleeding or clotting problems.
What symptoms should individuals look for following AstraZeneca vaccination?
You should speak to a health care professional if you have unusual or severe symptoms after any COVID-19 vaccine. If you experience any of the following symptoms between 4 and 28 days after your AstraZeneca vaccination, these symptoms might indicate that you have VITT (also referred to as a blood clot).
- Persistent and severe headache, seizures, blurred vision
- Focal neurological symptoms (Movement changes or sensation changes that affects specific functions, for example, weakness or loss of muscle control on the left or right side of the face, left or right arm, or even a small area such as the tongue, difficulty moving any part of your body)
- Problems with speech, vision, and hearing
- Shortness of breath
- Chest or severe abdominal pain or pain that does not go away
- New swelling, pain, or color change of an arm or a leg
- Bruising or pin point rash under the skin
These symptoms can also be a sign of other serious conditions and should be assessed in an emergency department.
Based on current evidence, for those individuals who have already been vaccinated with AstraZeneca more than 28 days ago there is no cause for concern.
What should you do if you have concerning symptoms after the AstraZeneca/COVISHIELD COVID-19 vaccine?
You should speak to a health care professional if you have unusual or severe symptoms after any COVID-19 vaccine. If your symptoms are not severe, you can see (virtually or in-person) your primary care professional. If you have severe symptoms, you should go to the nearest emergency department immediately. You should tell the health care providers who see you that you received the AstraZeneca/COVISHEILD COVID-19 vaccine and give them the date you got vaccinated. If the healthcare professional who assesses you is concerned, you may have scans and additional bloodwork collected.
Do healthcare professionals know how to diagnose and treat Vaccine-Induced Thrombotic Thrombocytopenia (VITT)?
Yes. Health care professionals and scientists in Newfoundland and Labrador have been working with experts in Canada, and around the world, to better understand VITT. Public Health has summarized what we know about VITT right now and has published guidelines for healthcare professionals outside and inside the hospital, to help them diagnose and treat VITT.
Will those who have received a first dose of AstraZeneca/COVISHIELD vaccine receive a second dose?
Before you decide which vaccine you will receive, consider the following information.
An mRNA vaccine is now preferred as the second dose for individuals who received a first dose of AstraZeneca/COVISHIELD. This is based on emerging evidence of better immune response from this mixed vaccine schedule, and to mitigate the potential risk of Vaccine-Induced Immune Thrombotic Thrombocytopenia (VITT) associated with viral-vector vaccines.
If you choose to complete the series with AstraZeneca/COVISHIELD vaccine, please review the following information:
Completing the series with AstraZeneca/COVISHIELD vaccine:
- Effectiveness: The same vaccine is generally used for all doses in a vaccine series because that is usually how the vaccine is studied by the vaccine companies. In clinical trials, the AstraZeneca/COVISHIELD COVID-19 vaccine prevented 60% to 80% of sickness from COVID-19 starting two weeks after the second dose. There was an even greater protection against hospitalization and death from COVID-19.
- Side Effects: Most reactions such as a headache and tiredness after getting AstraZeneca/COVISHIELD vaccine are mild or moderate and short-lived. These side effects are rarer and even milder after the second dose of the vaccine.
- Safety: A very rare but serious condition of blood clots combined with low levels of blood platelets (Vaccine-Induced Immune Thrombotic Thrombocytopenia, or VITT) has been reported following immunization with AstraZeneca/COVISHIELD or COVISHIELD vaccines in Europe, the United Kingdom, and Canada. These rare cases of VITT mostly happen between 4 and 28 days after the AstraZeneca/COVISHIELD vaccine. People who get an AstraZeneca/COVISHIELD vaccine should monitor for symptoms like severe and constant headache, belly pain, and difficulty breathing from 4 days to 42 days after the vaccine. In Canada, after the first dose, there has been one case of VITT reported for every 55,000 doses of vaccine given. The rate of VITT after a second dose is not clear yet, but after giving about 9 million second doses of AstraZeneca/COVISHIELD vaccine, the United Kingdom has reported 15 VITT cases. This is 1 case per 600,000 doses, which is much rarer than after first doses, however it is possible this could change over time.
Completing the vaccine series with an mRNA vaccine:
- Effectiveness: Most studies looking at giving an mRNA vaccine after a first dose of AstraZeneca/COVISHIELD are not finished yet, but one small study from Spain showed that immune response was greatly improved, compared with no second dose, when Pfizer vaccine was given 8 or more weeks after a dose of AstraZeneca/COVISHIELD vaccine. It is possible that using different vaccines might stimulate the immune system in different ways and provide a stronger immune response, but we don’t yet have studies that clearly prove this.
- Side Effects: A trial from the UK showed that people who got the Pfizer vaccine 4 weeks after a dose of AstraZeneca/COVISHIELD vaccine had more general reactions like fever and aches than those who received the same vaccine for their second dose. Most symptoms happened in the 2 days after immunization and went away on their own. In the study from Spain with AstraZeneca/COVISHIELD and then Pfizer after 8 weeks, side effects were mild and went away on their own.
- Safety: There have been no cases of VITT reported in NL after receiving an mRNA vaccine. There are no safety signals from either the UK trial or the one in Spain that gave people an mRNA vaccine after an AstraZeneca/COVISHIELD vaccine, however these trials were very small and there is less data on mixed vaccine series than on vaccine series with the same vaccine.
Currently, mRNA and AstraZeneca/COVISHIELD vaccine are both available in Newfoundland and Labrador. Therefore those who wish to have a second dose with mRNA will not be delayed in receiving that vaccine. If a person chooses an mRNA vaccine for their second dose, they do not need to restart a series. If a person needs help with understanding the information above, they may contact a healthcare professional.
Could other COVID-19 vaccines available in Newfoundland and Labrador cause vaccine-induced thrombotic thrombocytopenia (VITT)?
To date, there have been no confirmed cases of VITT with any other COVID-19 vaccine.