Australia’s drug regulator is reviewing reports of anaphylaxis related to the AstraZeneca coronavirus vaccine after five people experienced an allergic reaction after taking the drug.
Queensland health authorities reported that four people over the past two days potentially experienced anaphylactic reactions within 30 minutes of receiving the first dose of the AstraZeneca vaccine. Another case of allergic reaction was reported in Western Australia.
The reports prompted the Therapeutic Goods Administration (TGA) to announce a comprehensive review of coronavirus vaccine data to confirm the rate of anaphylaxis observed in Australia was consistent with the expected rate.
But the regulator said its advice following an initial review was that the vaccine should continue to be administered according to national guidelines.
The Western Australian chief health officer, Dr Andrew Robertson, said on Wednesday there had been one reported case of an allergic reaction in response to the AstraZeneca vaccine since it began being administered in that state. There have been 9,651 other doses given without reaction.
Robertson said the WA vaccine safety advisory committee had received two reports of individuals being treated with adrenaline for an allergic reaction following Covid vaccination. One of those had received the Pfizer vaccine – of which 13,291 other doses have been administered in WA without allergic reaction.
“Both have a history of previous allergic reactions and both individuals responded well to a single dose of adrenaline and recovered under observation without further incident,” Robertson said.
He added: “I want to reassure all Western Australians that the Covid vaccines being used in Australia are safe and effective.”
The Queensland health minister, Yvette D’Ath, also stressed the safety of the vaccines, saying the information about allergic reactions had been shared so that people who had a history of severe allergic reactions of anaphylaxis could choose to delay the vaccination, to make sure vaccine hub staff knew to discuss a history of allergic reactions, and to announce the extended observation time.
“Any other vaccine in this country, there are reactions to it, they are treated and we never hear about it,” D’Ath said.
Dr John Wakefield, the head of the Queensland health department, said allergic reactions to vaccines were “fairly rare” but “not a surprise”.
“The thing about this vaccination program is, nationally, if you are having the flu vaccine or any other type of vaccine and you have anaphylaxis, it is treated and you will never hear about it,” he said.
“Because there is so much focus on this, appropriately, on this vaccination, you are hearing about every single case that arises.
“So yes, we have had an anaphylaxis with Pfizer and we expect to get more. The issue with this is, you know, getting four within a 48-hour period, we think we probably need to have a closer look at that.”
At least 17 countries have suspended or delayed using the AstraZeneca vaccine after reports of blood clots in people who have received the shot.
The TGA’s head, Dr John Skerritt, said the European nations had taken an excessive approach. He told reporters in Canberra: “At this stage we don’t believe there is conclusive evidence for cause-and-effect on the clotting issue.”
Skerritt said almost 12 million people had been vaccinated with the AstraZeneca jab in the UK without any evidence of blood clots.
“We certainly don’t believe there is any specific problem around either AstraZeneca or Pfizer Covid vaccines,” he said.
Skerritt said allergic reactions had been extremely rare and there was no cause for concern for people with no history of anaphylaxis.
Current medical advice for both vaccines requires people without a previous history of specific or severe allergies to remain in the clinic for observation for 15 minutes after receiving the jab. The advice states that people with a history of allergic reactions should be vaccinated in a facility with medical staff in attendance, and observed for 30 minutes post-jab.
The TGA review will look at cases of allergic reaction to determine whether they are consistent with true anaphylaxis, examine the medical history of those affected to see if they have any history of allergies, and determine whether there is any clustering of common elements such as location, vaccine batch, age or sex.
Pre-release testing of the batch of the AstraZeneca vaccine that was sent to Queensland “confirmed that it was compliant with all requirements”, the TGA said.
Health authorities in Australia have administered more than 20,000 doses of the AstraZeneca vaccine and more than 163,000 doses of the Pfizer vaccine.
There have been 19 reports of anaphylaxis nationally: five following the use of the AstraZeneca vaccine and 14 following the Pfizer vaccine.
With Australian Associated Press