Canada halts AstraZeneca vaccine for those under 55

Canada yesterday suspended the use of the Oxford-AstraZeneca coronavirus vaccine for people under age 55 following concerns it might be linked to rare blood clots.

The National Advisory Committee on Immunisation had recommended the pause for safety reasons and the Canadian provinces, which administer health in the country, announced the suspension yesterday.

Dr Shelley Deeks, vice chairwoman of the National Advisory Committee on Immunisation said the updated recommendations come after new data from Europe that suggested the risk of blood clots is now potentially as high as one in 100,000, much higher than the one in one million risk believed before.

She said most of the patients in Europe who developed a rare blood clot after vaccination with AstraZeneca were women under age 55, and the fatality rate among those who develop clots is as high as 40 per cent.

Dr Joss Reimer of Manitoba’s Vaccine Implementation Task Force said despite the finding that there was no increase risk of blood clots overall related to AstraZeneca in Europe, a rare but very serious side effect has been seen primarily in young women in Europe.

Reimer said the rare type of blood clot typically happens between four and 20 days after getting the shot and the symptoms can mirror a stroke or a heart attack.

“While we still believe the benefits for all ages outweigh the risks I’m not comfortable with probably. I want to see more data coming out of Europe so I know exactly what this risk benefit analysis is,” Reimer said.

The AstraZeneca vaccine, which has been authorised in more than 70 countries, is a pillar of a UN-backed project known as Covax that aims to get Covid-19 vaccines to poorer countries.

It has also become a key tool in European countries’ efforts to boost their sluggish vaccine rollouts. That makes doubts about the shots especially worrying.

Health Canada said it has not received any reports of blood clots in Canada, and the department’s chief medical adviser, Dr Supriya Sharma, said she still believes the vaccine’s benefits outweigh the risks.