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Canada studying reports from Europe on AstraZeneca vaccine, blood clots


OTTAWA — Quebec Health Minister Christian Dubé rolled up his sleeve for the Oxford-AstraZeneca COVID-19 vaccine Thursday, a display of confidence in the injection that has recently been the focus of concerns over blood clots. 

His public vaccination in Montreal came hours after the European Medicines Agency declared a review found no evidence the AstraZeneca shot raises the overall risk of blood clots. 

"This is a safe and effective vaccine," said Emer Cooke, executive director of the European Medicines Agency. 

"Its benefits in protecting people from COVID-19, with the associated risks of death and hospitalization outweigh the possible risks. The committee also concluded that the vaccine is not associated with an increase in the overall risk of thromboembolic events or blood clots." 

Late Thursday, Health Canada said it has confirmed that the benefits of the AstraZeneca vaccine in protecting Canadians from COVID-19 outweigh the risks and encouraged people to get immunized with any of the vaccines that are authorized in the country.

Health Canada said in a release that it has assessed the available data and has determined that the AstraZeneca vaccine has not been associated with an increase in the overall risk of blood clots.

To date in Canada, it said there has been one report of a stroke in an individual following vaccination with the version of the AstraZeneca vaccine currently being distributed here.

"This case has been assessed by Health Canada and determined not to be related to the vaccine."

However, Europe is adding a warning label to the vaccine because there isn't any evidence yet to determine if it played any role in the development of rare blood clots in the brains of 18 patients who received it. Another seven patients who developed a rare condition that includes very low platelet counts and multiple small blood clots in veins throughout their body are also inconclusive, the agency said. 

"The evidence we have is, at the moment, not sufficient to conclude with certainty whether these adverse events are indeed caused by the vaccine or not," said Dr. Sabine Straus, chair of the agency's Pharmacovigilance and Risk Assessment Committee. 

She noted the cases were found in nearly 20 million vaccinations given in the United Kingdom, Europe and India. 

The U.K. Medicines and Healthcare Products Regulatory Agency issued similar news earlier Thursday, saying it firmly believes the vaccine is safe and effective but is doing a more detailed study looking at blood clots in the brain. 

Health Canada, which had officials at the European meeting Thursday morning, has not yet said if it intends to add a warning label here. 

Thrombosis Canada President Dr. James Douketis said the group's leadership team was meeting Thursday evening to discuss the European findings and would have an updated statement for Canadians no later than Friday. 

Last week Thrombosis Canada said there was no evidence linking the vaccine to blood clots and "strongly" recommended people get vaccinated. 

Douketis, an internal medicine physician specializing in blood clots at St. Joseph's Healthcare in Hamilton, said the number of incidents of blood clots has been very small, and he said COVID-19 can and does cause far more people to develop blood clots. 

Vaccinations are likely preventing a lot of blood clots by preventing people from getting COVID-19, he said. 

The first known report of a similar blood clot in Canada came Thursday, after a 79-year-old man in Quebec was admitted to hospital suffering from cerebral venous thrombosis, a blood clot in the vein that drains blood from the brain. 

The patient received the AstraZeneca vaccine several days earlier. 

Dubé said authorities are looking into the case but there is no link at this time between the condition and getting the vaccine. 

Earlier this week, Dr. Marc Berthiaume, the director of the medical sciences bureau at Health Canada, said the department had two reports of blood clots in patients who had received the vaccine from Pfizer-BioNTech. 

Blood clots do occur naturally in some patients, and there has been no known link to vaccines before the COVID-19 outbreak. 

More than 15 European countries had halted the use of AstraZeneca pending the EMA review. France, Germany and Italy all said they would resume those injections Friday. 

Before Europe's report was released Thursday, deputy chief public health officer Dr. Howard Njoo said Canada believed the vaccine was safe and effective. 

"The fact is that all four COVID-19 vaccines authorized by Health Canada meet our country’s high standards for safety, and provide a high degree of protection against severe illness and death related to COVID-19," said Njoo. 

Cooke said the warning label is not meant to advise people against getting the vaccine but to raise awareness so people who do get it are told what signs to look out for when it comes to blood clots. 

"If it was me, I would be vaccinated tomorrow," she said. 

Cooke said there are thousands of people dying every day from COVID-19 and this vaccine is effective against the novel coronavirus. 

Canadian provinces began administering 500,000 doses of the AstraZeneca vaccine last week. Canada's doses are not made in the same place as the European or U.K. doses. 

Thrombosis Canada issued a statement March 11 saying in general vaccines are not linked to the development of blood clots and it had no evidence that the AstraZeneca vaccine was any different. 

This report by The Canadian Press was first published March 18, 2021. 

Mia Rabson, The Canadian Press

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