May 11, 2021
By Christine Ross
Ontario is pausing the first dose of AstraZeneca starting immediately out of concern over rare blood clots. Provincial science adviser Dr. Jessica Hopkins says new data shows the risk of blood clots has increased to one in 60,000.
“When you look at it on a large scale our risk of a side effect from the VITT has gone from one in 105,00 to one in 60,000 and that’s a significant safety signal we don’t want to ignore,” said Dr. Hopkins.
In Canada, at least twelve rare clot cases have been confirmed, eight of them in Ontario and three women have died across the country.
No details yet on what those who’ve already received an AstraZeneca shot will get for the second dose.
UK data indicates risk is much lower if it’s used as a second dose at one in a million.
Mixing doses is being studied and Medical Officer of Health Dr. David Williams says he’ll offer more direction for the second dose in the coming weeks.
Ontario currently has 50-thousand doses of AstraZeneca but has no confirmation when more supply is coming.