Federal health officials say Canadians should not feel skittish about rolling up their sleeves to get a shot of the AstraZeneca COVID-19 vaccine or its Indian-produced twin, Covishield, because their benefits far outweigh the risks of developing very rare and potentially fatal blood clots.
In a statement released on Wednesday, Health Canada said its ongoing safety review of blood clots associated with low levels of blood platelets following immunization with AstraZeneca and Covishield found that “these very rare events may be linked to use of the vaccine.”
As a result federal regulators have updated the product label to warn would-be patients about the risk of developing these clots. Patients who receive the shot will be told to look out for symptoms — severe headaches, abdominal pain, leg pain or shortness of breath, the statement said.
“The potential risk of these events is very rare, and the benefits of the vaccine in protecting against COVID-19 outweigh its potential risks,” the statement said.
“In the very rare event that someone experiences unusual blood clots with low platelets, there are treatments available.”
The National Advisory Committee on Immunization (NACI) is also reviewing the available information to determine whether to maintain or modify its current recommendation not to use the vaccine in people under 55, the statement added.
Denmark stops using AstraZeneca
The statement by Health Canada came on the same day as health authorities in Denmark announced that they will stop using AstraZeneca’s COVID-19 vaccine altogether over a potential link to this rare but serious form of blood clot.
Results of investigations into the AstraZeneca-associated blood clots “showed real and serious side-effects,” Danish health agency head Soren Brostrom told a news briefing.
“We have therefore chosen to continue the vaccination programme for all target groups without this vaccine,” Brostrom said.
The European Union’s drug watchdog said last week it had found a possible link between the AstraZeneca vaccine and cerebral venous sinus thrombosis (CVST), a brain blood clot.
It said the risk of dying from COVID-19 was much greater than the risk of mortality from rare side effects, but left it to individual states to make their own risk assessments and decide how to administer the vaccine.
Many countries in Europe and elsewhere have resumed using the shot, with some restricting it to certain age groups, mostly those aged above 50 or above 60.
Brostrom said joint studies based on Danish and Norwegian health data estimated that one in 40,000 people vaccinated with the AstraZeneca shot could expect to experience this serious complication, with nothing conclusive related to age or gender.
So far, only one Canadian, a woman in Quebec, has developed clots after receiving the Covishield vaccine produced by the Serum Institute of India.
With files from Reuters