Five people who received a COVID-19 vaccine have developed blood clots in the past week.
The Therapeutic Goods Administration believes all their illnesses are related to their doses of the AstraZeneca vaccine.
They are 74-year-old man and 51-year-old woman in Victoria, a 66-year-old man in Queensland, a 70-year-old man in Tasmania and a 64-year-old woman from Western Australia,
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They have all been hospitalised, with the man in Queensland currently being treated in the Townsville Hospital intensive care unit.
Australia has now recorded 11 cases of blood clots in AstraZeneca vaccine recipients since the roll-out started, from about 1.4 million doses.
One of the cases was fatal, that of a 48-year-old NSW woman in April.
Four of five people who developed blood clots from their vaccines in the week prior to the last have been released from hospital.
“The adverse event remains very rare. It remains at a frequency that’s similar to that reported by other countries using AstraZenec vaccine,” TGA head John Skerritt said on Thursday.
Skerritt said there was nothing unusual about a small number of over 50s developing rare blood clots after receiving AstraZeneca vaccine.
He said the risk of COVID-19 was far greater to older people than adverse reactions to vaccines.
“If you’re only giving a medicine or vaccine for people over 50, that’s the only group who will see an adverse event,” he said.
“By being vaccinated we’re not only protecting ourselves, but we’re also protecting our loved ones, especially the older, more frail ones, and those around us in the community.”
AstraZeneca said it is aware of the new clotting cases and will “continue to support regulators in Australia and overseas”.
“Tens of millions of people have now received our vaccine across the globe,” the company said in a statement.
“The extensive body of data from two large clinical datasets and real-world evidence demonstrate its effectiveness, reaffirming the role the vaccine can play during this public health crisis.
"‘The adverse event remains very rare.’"
“Our global commitment remains to play an important role in addressing the current global health emergency posed by COVID-19 by providing a safe and effective vaccine, at no profit during the pandemic.”
More than 550,000 doses of vaccine have been distributed to around 3000 sites across the country this week.
Despite the clotting cases, health authorities are aiming to increase the number of weekly vaccines by about 270,000 doses.
- With AAP