Several countries have made the decision to suspend the use of the Oxford-AstraZeneca Covid-19 vaccine over blood clot concerns after cases of recipients suffering severe side effects in the days and weeks following their first dose.
At least 10 European countries have now taken the step to suspend or limit the use of the jab after reports of potential side effects. Austria was the first to make the choice to halt a single batch of the vaccine on 7 March as a result of one individual aged below 50 having reportedly died with blood clots shortly after receiving their dose.
It wasn’t long after that Norway followed by halting the vaccine altogether, with a review from their medicines agency showing four new cases of “serious blood clotting in adults.”
Demark and Iceland then took the same action, along with Bulgaria and Thailand on March 12, after the death of a woman in Demark and proposed thromboembolic events that can occur when blood clots prevent normal circulation.
Denmark’s Health Minister, Magnus Heunicke said, “it is currently not possible to conclude whether there is a link. We are acting early, it needs to be thoroughly investigated.”
Germany, France, Italy, Spain, Indonesia, Sweden, and the Netherlands all suspended the shot on March 15, with Dutch authorities announcing 10 cases of similar problems reported by those who received the jab. The other countries have stated that their actions are precautionary.
German Health Minister, Jens Spahn said, “this is a professional decision, not a political one.”
The Republic of Ireland has also paused its use but health officials in Northern Ireland have said they will continue to use the vaccine. There are also other countries, including the UK, that are continuing its use.
Despite the reported cases and potential fear surrounding severe side effects, the European Medicines Agency (EMA) and the World Health Organisation (WHO) have said there is no evidence so far that the adverse effects, including at least five deaths, were caused by the vaccine.
Both the EMA and WHO state that the vaccine should be continued as the benefits of inoculation outweigh the current risks. They are currently probing these incidents and are expected to issue reports on their findings.
The WHO says, “as of today, there is no evidence that the incidents are caused by the vaccine.” Even so, national governments have decided to take precautionary action, and experts have warned that its suspension is likely to influence public confidence in the vaccine.
Penelope Ward, a professor of Pharmaceutical Medicine at London’s King’s College, has reviewed the UK Medicine regulators collected data and reports, “in the UK, about 165 people a day might suffer a thrombotic episode, some of which will be fatal. In contrast, the number of reports from the ongoing vaccine programme in the UK and EU, which includes more than 20 million, is just 37.”
Megan Ranney, a professor of Public Health and Emergency Medicine at Brown University, concurs with this saying that at this stage, there is “minimal biological plausibility” for why the vaccine could cause blood clots.
David Spiegelhalter, Chair of the Winton Centre for Risk and Evidence Communication at the University of Cambridge, warned the importance of not jumping to conclusions: “Of course a possible link should be looked at very carefully, but we must be wary not to assume one event caused another, just because one followed another.”
Professor Stephen Evans of the London School of Hygiene and Tropical Medicine also refers to cause and effect: “The problem with spontaneous reports of suspected adverse reactions to a vaccine as the enormous difficulty of distinguishing a causal effect from a coincidence.”
AstraZeneca has also responded to concerns with a statement after a review of all the available data that included there’s “no evidence of an increased risk of pulmonary embolism, deep vein thrombosis, or thrombocytopenia, in any defined age group, gender, batch, or in any particular country.”
“We’re closely reviewing reports but given a large number of doses administered, and the frequency at which blood clots can occur naturally, the evidence available does not suggest the vaccine is the cause.”
Danielle Saunders
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