A medical worker holds a syringe and a vial of the AstraZeneca-Oxford COVID-19 vaccine, on March 9, 2021.MIGUEL MEDINA/AFP/Getty Images
Denmark and Norway have suspended the use of the Oxford-AstraZeneca vaccine in yet another blow to Europe’s stumbling vaccine rollout.
The Danish and Norwegian moves Thursday came after Austria suspended the use of a specific batch of the AstraZeneca vaccine because a patient was diagnosed with multiple thrombosis (blood clots) and died 10 days after being vaccinated with the product. Another patient suffered a pulmonary embolism but is recovering.
In a statement published Wednesday, after Austria suspended the use of the vaccine, the European Medicines Agency (EMA) said, “There is currently no indication that vaccination has caused these conditions, which are not listed as side effects with this vaccine.”
The EMA said: “The information available so far indicates that the number of thromboembolic events in vaccinated people is no higher than that seen in the general population,” adding that, as of March 9, 22 thromboembolic cases had been reported among the three million people who had received the AstraZeneca vaccine.
In Italy, national and Sicilian media have reported the deaths of two Sicilian men a few days after receiving the AstraZeneca vaccine. According to a report from Reuters, Italian health authorities ordered the withdrawal of a batch of AstraZeneca vaccine after the deaths, but it was a precautionary measure and no direct link had been established. Local media reported that a 43-year-old navy officer died of a heart attack the day after his shot and a 50-year-old policeman died some 12 days after being diagnosed with deep vein thrombosis after his jab.
Canada pre-purchased millions of doses of seven different vaccine types, and Health Canada has approved four so far for the various provincial and territorial rollouts. All the drugs are fully effective in preventing serious illness and death, though some may do more than others to stop any symptomatic illness at all (which is where the efficacy rates cited below come in).
- Also known as: Comirnaty
- Approved on: Dec. 9, 2020
- Efficacy rate: 95 per cent with both doses in patients 16 and older, and 100 per cent in 12- to 15-year-olds
- Traits: Must be stored at -70 C, requiring specialized ultracold freezers. It is a new type of mRNA-based vaccine that gives the body a sample of the virus’s DNA to teach immune systems how to fight it. Health Canada has authorized it for use in people as young as 12.
- Also known as: SpikeVax
- Approved on: Dec. 23, 2020
- Efficacy rate: 94 per cent with both doses in patients 18 and older, and 100 per cent in 12- to 17-year-olds
- Traits: Like Pfizer’s vaccine, this one is mRNA-based, but it can be stored at -20 C. It’s approved for use in Canada for ages 12 and up.
- Also known as: Vaxzevria
- Approved on: Feb. 26, 2021
- Efficacy rate: 62 per cent two weeks after the second dose
- Traits: This comes in two versions approved for Canadian use, the kind made in Europe and the same drug made by a different process in India (where it is called Covishield). The National Advisory Committee on Immunization’s latest guidance is that its okay for people 30 and older to get it if they can’t or don’t want to wait for an mRNA vaccine, but to guard against the risk of a rare blood-clotting disorder, all provinces have stopped giving first doses of AstraZeneca.
- Also known as: Janssen
- Approved on: March 5, 2021
- Efficacy rate: 66 per cent two weeks after the single dose
- Traits: Unlike the other vaccines, this one comes in a single injection. NACI says it should be offered to Canadians 30 and older, but Health Canada paused distribution of the drug for now as it investigates inspection concerns at a Maryland facility where the active ingredient was made.
How many vaccine doses do I get?
All vaccines except Johnson & Johnson’s require two doses, though even for double-dose drugs, research suggests the first shots may give fairly strong protection. This has led health agencies to focus on getting first shots to as many people as possible, then delaying boosters by up to four months. To see how many doses your province or territory has administered so far, check our vaccine tracker for the latest numbers.
The EMA has launched an investigation into the product to determine if the deaths and illnesses were vaccine-related. The quality of the batch used in Austria will be inspected for possible defects.
The same batch of one million doses, known as ABV5300, was used in 16 other countries in the European Union, including Spain, Sweden and the Netherlands.
According to the EMA, that particular batch was not used in Italy. But the Italian drug regulator halted the use of a separate batch, ABV2856, after the two Sicilian deaths.
Austria intends to suspend its use for 14 days while the investigation takes place. By Thursday, seven European countries, including Iceland, Estonia and Luxembourg, had halted the use of the ABV5300 batch. The Spanish Health Ministry said it would continue to administer doses from the batch because it was unaware of any related cases of blood clots.
The AstraZeneca product is one of three available in the EU; the others are made by Pfizer-BioNTech and Moderna.
The AstraZeneca vaccine has also been approved for use in Canada, however no shipments have arrived yet. The country is receiving the same drug made using a different manufacturing process in India, where it is called Covishield.
On Thursday, the EMA approved the one-dose Johnson & Johnson vaccine, though supply constraints will ensure that its EU rollout will be slow.
In an interview, Pierre Morgon of MRGN Advisors, a Swiss-based biotech and vaccine consultancy, said: “This is a reminder that the safety database of a novel medication isn’t comprehensive until there’s a very large number of people having used the medication, representing all, or almost all, medical situations and conditions.”
Typically, vaccines and other medications are developed through clinical trials with inclusion and exclusion criteria. Any adverse effects among people with medical conditions excluded from the trials would not be known until after a product was approved and made available to the public.
AstraZeneca said patient safety was its “highest priority” and that the vaccine “has been extensively studied in Phase 3 clinical trials and peer-reviewed data confirms the vaccine has been generally well tolerated.”
The suspensions of the use of the product, which has been ordered in far greater quantities by governments around the world than any other vaccine, will inevitably slow the European vaccination campaign. According to the Bloomberg Vaccine Tracker, the EU has administered doses to less than 10 per cent of the population. Vaccination rates in the U.K. and the U.S. are three times higher.
In London trading, AstraZeneca shares lost 2.7 per cent.
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