COPENHAGEN (Reuters) – Health officials in Denmark, Norway and Iceland on Thursday suspended the use of AstraZeneca’s COVID-19 vaccine after reports of blood clots forming in some people who had been vaccinated.
Austria had stopped using a batch of AstraZeneca injections while investigating a death from coagulation disorders and a disease from pulmonary embolism.
Still, the European drug regulator EMA said the vaccine’s benefits outweigh its risks and could continue to be administered.
Europe is struggling to accelerate the launch of a vaccine after delays in the delivery of Pfizer and AstraZeneca, despite an increase in cases amid a more contagious virus variant that has triggered new blockages in countries like Italy and France.
Denmark suspended vaccines for two weeks after a 60-year-old woman, who received an AstraZeneca injection from the same batch used in Austria, formed a blood clot and died, Danish health officials said.
Their response was also prompted by reports of “possible serious side effects” from other European countries.
“It is currently not possible to conclude whether there is a link. We are acting early, he needs to be investigated thoroughly, ”said Health Minister Magnus Heunicke on Twitter.
The vaccine would be suspended for 14 days in Denmark.
“This is a cautious decision,” said Geir Bukholm, director of infection prevention and control at the Norwegian Institute of Public Health (FHI), at a news conference.
FHI did not say how long the suspension would last.
“We … await information to see if there is a link between vaccination and this case with a blood clot,” said Bukholm.
Iceland on Thursday suspended vaccine jabs pending the results of an EMA investigation. Italy, also on Thursday, said it would suspend the use of an AstraZeneca lot other than that used in Austria.
Some health experts said there was little evidence to suggest that the AstraZeneca vaccine should not be administered and that cases of blood clots corresponded to the rate of such cases in the general population.
“The problem with spontaneous reports of suspected adverse reactions to a vaccine is the enormous difficulty in distinguishing a causal effect from a coincidence,” Stephen Evans, professor of pharmacoepidemiology at the London School of Hygiene & Tropical Medicine, told Reuters.
Evans added that COVID-19 disease was strongly associated with blood clotting.
Phil Bryan, head of the UK’s Medicines and Health Products Regulatory Agency (MHRA), said reports of blood clots so far do not exceed what would have occurred naturally in the vaccinated population.
“The available evidence does not confirm that the vaccine is the cause,” he said.
More than 11 million doses of the AstraZeneca vaccine have been administered so far across the UK.
In a statement, AstraZeneca said it found no evidence of an increased risk of pulmonary embolism or deep vein thrombosis in safety data from more than 10 million records, even considering subgroups based on age, sex, production lot or country of use.
“In fact, the observed number of these types of events is significantly lower in those vaccinated than would be expected among the general population,” he added.
The drugmaker said this week that “there have been no confirmed serious adverse events associated with the vaccine”. He said he was in contact with the Austrian authorities and would fully support the investigation.
The European Union’s drug regulator, EMA, said on Wednesday that there was no evidence so far linking AstraZeneca to the two cases in Austria.
He said the number of thromboembolic events – marked by the formation of blood clots – in people who received the AstraZeneca vaccine was not greater than that seen in the general population, with 22 cases reported among the 3 million people who received the vaccine as March 9th.
The EMA said it understood that the decision by Denmark and Norway was taken as a precaution.
Four other countries – Estonia, Lithuania, Luxembourg and Latvia – have suspended inoculations of the batch while investigations continue, the EMA said.
The batch of 1 million doses went to 17 EU countries.
Swedish officials said they did not find enough evidence to stop vaccination with the AstraZeneca vaccine.
“There is nothing to indicate that the vaccine causes this type of blood clot,” said Veronica Arthurson, head of drug safety at the Swedish Medical Products Agency, at a news conference.
The Danish Medicines Agency said it started an investigation into the vaccine together with corresponding agencies in other EU countries and the EMA.
So far, 138,148 Danes have received an injection with the AstraZeneca vaccine in a country of 5.8 million people. The Nordic country, which also uses vaccines from Pfizer-BioNTech and Moderna, is expected to receive 2.6 million doses of AstraZeneca in the coming months.
The Danish Health Authority said the final date for when it expects all Danes to have been fully vaccinated will be postponed by four weeks to 15 August.
Spain said on Thursday that it has not registered any cases of blood clots related to the AstraZeneca vaccine so far and that it will continue to administer the vaccines.
(Reporting by Nikolaj Skydsgaard and Jacob Gronholt-Pedersen in Copenhagen and Victoria Klesty in Oslo; Additional reporting by Ludwig Burger in Frankfurt, Johan Ahlander in Stockholm, Crispian Balmer in Rome and Kate Kelland in London. Editing by Alex Richardson, Nick Macfie and Bernadette Baum)