Astrazeneca doses set to expire, causing concern
The rate of blood clotting from the Astrazeneca or Covishield vaccine — the same product, just made in different places — is between one in 60,000 doses, per Ontario, and one in 100,000 doses, per the National Advisory Committee on Immunization.
After provinces across the country suspended the use of the Astrazeneca vaccines over rare blood clots, there is some concern that thousands of doses could expire before they can be used.
In Ontario, the government hasn’t yet made a clear decision about what it’s going to do with the up to 50,000 doses of Astrazeneca that have gone unused since injections were halted last week. At least 30,000 doses that are sitting in Ontario pharmacies are set to expire at the end of May.
“We have a very limited window to put in place and execute a strategy looking at all the options,” said Justin Bates, president of the Ontario Pharmacists Association.
The OPA is calling on the province to allow the shots to be used for first or second doses, or to ship them to another country.
“Those are the three primary options that are available to us, or, of course, letting it go to waste, which I don’t think anyone wants to pursue,” Bates said. “We’re hopeful … we’ll get direction and we’ll be able to help get those doses in arms.”
Astrazeneca recommends a four- to 12-week interval between doses. At 12 weeks, the immune response is strongest, offering 85 per cent protection against serious illness from COVID-19; at earlier weeks, that protection drops to 68 or 69 per cent. Canada is currently spacing out shots by four months.
Ontario is currently exploring whether or not to offer Astrazeneca as a second dose, or mix-and-match different vaccines. In order to use up doses by the end of May, public health officials might also need to reduce the interval between doses.
The Ontario government didn’t respond to Postmedia’s request for comment by press time, but Dr. David Williams, Ontario’s chief medical officer of health, alluded to the issue of expiration — though he didn’t address it full on — when asked about intervals between Astrazeneca vaccines. He said the province hopes to give the second dose 12 or more weeks after the first.
“At the same time, I’m not willing to wait and give expired vaccine at all, under any means, to anyone in Ontario. That would be totally wrong,” Williams said.
Roughly 2.1 million Canadians have received the Astrazeneca vaccine so far, says the Public Health Agency of Canada (PHAC).
Last week, Maj.-gen. Dany Fortin, then the head of the national vaccine rollout, said that there were 250,000 Astrazeneca doses left in the country — and most of them were expiring at the end of June.
“So, there’s still time for them to be used as a second dose,” Fortin said.
The issues of supply and expiration seem to be less acute outside Ontario, because other jurisdictions that suspended first doses are continuing to offer second doses, meaning the on-hand stock will continue to be used.
That includes 7,700 doses in Alberta and around 20,000 doses in British Columbia.
In Manitoba, some portion — government officials couldn’t specify how much — of the remaining 6,700 doses will expire at the end of May, but the rest are good until the end of June.
Distribution of those vaccines, the province said, lies with pharmacies and medical clinics.
“We are fully confident they will administer soon to expire doses as per eligibility of client,” a spokesperson said.
The country is expecting another 655,000 doses of Astrazeneca to arrive this week, even as the vaccine’s usage is being studied by health officials countrywide. But those vaccines won’t expire until August, PHAC said.
The rate of blood clotting from the Astrazeneca or Covishield vaccine — the same product, just made in different places — is between one in 60,000 doses, per Ontario, and one in 100,000 doses, per the National Advisory Committee on Immunization.