AstraZeneca vaccines in Canada have been halted due to warnings of blood clotting.

AstraZeneca vaccines in Canada have been halted due to warnings of blood clotting.

On Tuesday, Ontario, Canada’s largest province, declared that it will no longer have first doses of the Covid-19 vaccine produced by AstraZeneca-University of Oxford, citing reports that the incidence of unusual blood clots remains greater than previously thought.

Dr. David Williams, Ontario’s chief medical officer for health, said the decision was taken out of concern due to an uptick in cases of an unusual blood clotting condition related to the shot.

“There have been more news in the last few days. We’re looking at the evidence to see how the AstraZeneca vaccine should be used for second doses and more broadly,” he added.

AstraZeneca’s Covid-19 vaccine is still being limited in several European countries due to related issues. Out of more than 2 million doses given in Canada, at least 12 cases have been confirmed, with three women dying.

Dr. Williams, on the other hand, believes that those who got their first injection of the AstraZeneca vaccine did all they could to protect their family, loved ones, and neighborhoods.

The vaccine’s advantages have consistently outweighed any drawbacks, according to Canada’s health regulator. Justin Trudeau, the Prime Minister of Canada, and Doug Ford, the Premier of Ontario, also got their first injection of AstraZeneca’s vaccine recently.

Mr Trudeau claims that almost half of all qualifying adults in Canada have had at least one coronavirus vaccine injection. Pfizer and Moderna are responsible for the majority of this. He claims that by the end of the summer, Canada will have enough vaccines to ensure that any qualifying citizen has had their first injection, and that by September, it will have enough doses to ensure that everyone is properly vaccinated.


AstraZeneca’s vaccine was also suspended in Alberta, but this time due to speculation regarding the delivery of further imports, not because of fears about side effects.

So far, Canada has delivered just over 20 million doses of different Covid-19 vaccines, with AstraZeneca’s vaccine accounting for 11.6 percent. Alternative vaccines, such as Pfizer and Moderna, have promised to send more than enough vials to vaccinate any Canadian with two doses in the future.

Following the announcement that AstraZeneca’s vaccine will no longer be used in Ontario, several social media users proposed sending any leftover vaccines to India, which is dealing with a serious second wave of Covid-19.

No way.

“Humble suggestion: Ontario should give excess AstraZeneca doses to India to help avert a humanitarian crisis,” tweeted Naheed Dosani, a Toronto-based palliative care physician.

Many people have expressed concerns regarding the 850,000 people in Ontario who have already received the AstraZeneca vaccine.

In a series of tweets, Ahmed Ali, a Toronto-based academic, stated that “powerful and inclusive science communication isn’t as difficult as Ontario makes it out to be.”

“Thinking about all who had the AstraZeneca vaccine in Ontario. The decision to halt first doses was made without empathy or sensitivity today. Mr Ali said, “I’m not sure who wants to hear this, but getting the AstraZeneca vaccine was a smart idea, but don’t overthink it.”

About 1.28 million cases of Covid-19 have been recorded in Canada since the outbreak began, with over 24,600 deaths.

What to talk about the side effects of the Oxford-AstraZeneca vaccine
Vaxzevria, a COVID-19 vaccine developed by the University of Oxford and AstraZeneca, may cause some of the common mild-to-moderate side effects associated with vaccinations. However, there have been several recent debates about the vaccine’s connection to rare blood clotting events.

At the time of publishing, all data and figures is focused on publicly accessible information. It’s possible that some of the material is outdated. For the most up-to-date information on the COVID-19 pandemic, visit our coronavirus hub and follow our live updates stream.

The Oxford-AstraZeneca COVID-19 vaccine, also known as Vaxzevria as of March 25, 2021, is a two-dose vaccine developed in collaboration with the Oxford Vaccine Group and pharmaceutical firm AstraZeneca to combat the SARS-CoV-2 virus.

The COVID-19 vaccine from the Serum Institute of India, known as Covishield, is a localized variant of the Oxford-AstraZeneca vaccine.

The key review of phase 3 trial data by AstraZeneca

The European Commission granted the vaccine “conditional marketing permission” in the European Union for adults aged 18 and over on January 29, 2021, following a recommendation from the European Medicines Agency (EMA). On February 15, the World Health Organization (WHO)Trusted Source released the vaccine’s “emergency use listing.”

The gene for the spike protein on the surface of the SARS-CoV-2 virus is encoded in this viral vector vaccine. As the gene is released to our cells, it is transcribed, causing our cells to produce the spike protein. The presence of this protein causes the immune system to develop antibodies to combat the spike protein, which then prepares the body to fight the spike protein.


Side effects that are common
The most frequent side effects, according to the vaccine’s safety profile in the product information, are mild-to-moderate symptoms of one or more of the following:

a migraine (52.6 percent )
exhaustion (53.1 percent )
pressure in the muscles or joints (44 percent or 26.4 percent )
febrile illness (33.6 percent )
shivers (31.9 percent )
stomach ache (21.9 percent )
The figures are based on data from four research trials involving a total of 23,745 people.

Individuals also complained of discomfort and irritation at the injection site.

Additionally, an adverse reaction to such vaccine formulations is possible. Hives, a rash, swelling, and respiratory effects are also signs of an allergic reaction.

Anaphylaxis, a serious and potentially life-threatening allergic reaction, has also been reported in a few cases. Anaphylaxis, on the other hand, is a very rare occurrence.

Just 455 (0.002%) of 19.5 million Vaxzevria doses is linked with an anaphylaxis-related adverse reaction, according to the Medicines and Healthcare Goods Regulatory Agency (MHRA).

The vaccination is not recommended for those who have documented reactions to either of the ingredients — either the active agent or any of the ingredients specified under the prescription information’s “List of excipients.”

Many of the aforementioned side effects are close to those seen in other vaccines, according to the Centers for Disease Control and Prevention.

Blood clots are a source of contention.
Following warnings of serious blood clots, the Danish Health Authority placed vaccination with Vaxzevria on hold in early March 2021.

Following the administration of Vaxzevria to approximately 5 million citizens in the European Economic Region, the EMA reported 30 cases of blood clots, or thrombosis. One of these cases resulted in death in Denmark.

The EMA found thrombosis cases in conjunction with thrombocytopenia, a syndrome characterized by reduced blood platelet counts. Many forms of thrombosis were also discovered, including uncommon instances of cerebral venous sinus thrombosis, a rare form of blood clots in the brain.

On April 7, 2021, the European Medicines Agency’s (EMA) safety advisory committee decided that irregular blood clots and low blood platelets should be identified as very rare side effects of Vaxzevria, implying a possible causal association.

The benefits of the vaccine, according to the EMA, appear to overshadow the dangers by avoiding SARS-CoV-2 infection.

As of March 31, the MHRA had received 79 complaints of blood clotting cases with reduced platelet levels in the United Kingdom. All of these events happened after the first dose was given, and 19 of them were fatal.

51 of the 79 incidents involved women, with the majority of them occurring in people under the age of 50. The MHRA did point out, though, that a larger number of people were affected.

The EMA indicates that the cumulative events of blood clots and reduced blood platelet counts could be a form of immune reaction, despite the fact that regulatory authorities have not listed known risk factors for blood clotting.

Individuals and healthcare providers should be aware of the signs of thrombosis, according to regulatory authorities, to ensure timely diagnosis and treatment.

Thromboembolic activities can cause a variety of symptoms, including:

Breathing problems
abdominal pain leg swollen lung pain
headaches and blurred vision are examples of neurological problems.
Beyond the vaccine injection site, there are small blood stains under the surface.
COVID-19 vaccination is currently permitted in 83 countries.

At the time of publishing, all data and figures is focused on publicly accessible information. It’s possible that some of the material is outdated. For the most up-to-date information on the COVID-19 pandemic, visit our coronavirus hub and follow our live updates stream.

As the global initiative to develop vaccines to combat the COVID-19 pandemic progresses, headlines begin to illustrate both development advances and safety issues.

This article outlines the documented side effects of the 13 vaccines that have been approved, as well as dangers that researchers are still looking into.

Stay up to date on the latest COVID-19 epidemic with real-time alerts, and visit our coronavirus center for more information on prevention and treatment.

Currently authorized COVID-19 vaccines

The table below gives an overview of the 13 authorized vaccines, categorized by type, based on how they function. It also shows their efficacy.

Each of the following vaccines has received use authorization in at least one country.

NameManufacturerType of vaccineEfficacy rate
Ad26.COV2.SJanssen (Johnson & Johnson)Viral vector66%
AZD1222Oxford-AstraZenecaViral vector81.3%Trusted Source
Covishield*Serum Institute of IndiaViral vector81.3%
Ad5-nCovCanSinoViral vector65.28%
Sputnik VGamaleyaViral vector91.6%Trusted Source
CovaxinBharat BiotechInactivated80.6%
BBIBP-CorVSinopharm (Beijing)Inactivated79.34%Trusted Source
Inactivated (Vero Cell)Sinopharm (Wuhan)Inactivated72.51%
RBD-dimerAnhui Zhifei LongcomProtein subunitUnknown
EpiVacCoronaFBRIProtein subunitUnknown

Anaphylaxis and allergic reactions
An allergic reaction to one or more of the components in a vaccine occurs infrequently. Hives or some kind of skin rash, swelling, and respiratory problems are all possible.

Anaphylaxis is an extreme allergic reaction characterized by low blood pressure, fatigue, and trouble breathing, among other symptoms.

Anaphylaxis is a very unusual reaction to a vaccine. According to the CDC, about 2–5 people a million, or less than 0.001% of people vaccinated in the United States, have reported anaphylaxis as a result of the vaccine.

Since they contain a chemical called polyethylene glycol (PEG), which has never been used in an authorised vaccine before, allergic reactions to mRNA vaccines have been a source of concern. Many medications contain PEG, which has caused anaphylaxis in certain people. It wraps the mRNA molecule in these vaccines, allowing it to penetrate cells.

Similar questions have been raised regarding the Janssen vaccineTrusted Source, which includes polysorbate 80, a chemical with a similar structure to PEG.

a research paper

Most patients who developed anaphylaxis after receiving the mRNA COVID-19 vaccine had a history of allergies and this particular serious reaction, according to a trusted source of evidence on allergic reactions to mRNA COVID-19 vaccines.

According to the findings, mRNA COVID-19 vaccines pose a very low risk of anaphylaxis. Regardless, the CDC’s Trusted Source recommends that vaccine managers test for specific allergic responses before administering vaccines. People with allergies to diets, livestock, natural elements, latex, and oral prescriptions should safely use these vaccinations.

According to the CDC, someone who has experienced an adverse response to one dose of a vaccine does not get a second dose of the same vaccine.

Women’s side effects: how common are they?

Women tend to experience side effects more often than men. According to CDC researchers, women were included in 78.7% of Trusted Source adverse effect cases submitted within the first month of vaccination in the United States.

Females accounted for 15 out of 16Trusted Source people who developed anaphylaxis after receiving a vaccine, according to another report.

These results are consistent with a 2013 report on the H1N1 vaccine during the 2009 flu pandemic, which showed that females of childbearing age had higher rates of hypersensitivity reactions than other populations in the study community.

Estrogen and testosterone, two reproductive hormones, can play a role in this sex disparity. a research paper In mice, there is a reliable source.

Are vaccines successful in preventing variants?
The meaning of the term “job” contains the answer to this question. When vaccine researchers lay down the terms of their clinical trials, they collaborate closely with regulatory agencies including the Food and Drug Administration (FDA) to guarantee that the most pressing issues are addressed.

The primary endpoints, or key questions that a clinical trial raises, for most experimental COVID-19 vaccines is COVID-19 prevention. This meant that when determining how well their vaccine candidate worked, the developers would consider every case of COVID-19, even mild and severe cases.

Eight people who received the Pfizer-BioNTech vaccine, which was the first to obtain emergency use authorization from the FDA, developed COVID-19, while 162 people who received the placebo developed COVID-19. This translates to a vaccine effectiveness rate of 95%.

By the time the data was published in the New England Journal of Medicine on December 31, 2020, there had been no deaths in either category in the clinical trial that the researchers could attribute to COVID-19.

Real-world evidence from Israel suggests that this vaccine is particularly effective in combating COVID-19, including serious illness, according to a new report.

B.1.1.7, a SARS-CoV-2 variant first discovered in the United Kingdom, is one of a handful of new SARS-CoV-2 variants causing concern. B.1.351, which was first discovered in South Africa, and P.1, which seems to have originated in Brazil, are two other varieties that have caused concern.

These variants are concerning because they tend to be more transmissible than previous variants, and there is speculation that some of them may lead to more serious COVID-19 cases.

Two key issues have arisen as a result of these concerns: Would COVID-19 vaccines still on the market be able to balance these new variants? How would vaccine manufacturers alter their candidates to react to n?