Australian health authorities insist the AstraZeneca coronavirus vaccine is safe despite a host of European nations halting its rollout over fears it can cause serious side-effects.
Germany, France and Italy are the latest nations to halt their rollouts after reports of isolated cases of bleeding, blood clots and a low platelet count in recipients.
Denmark, Norway, Iceland, Bulgaria, Ireland and the Netherlands have also suspended the vaccine until further notice.
Australia has acquired more than 50 million doses of the vaccine, which will be in production on our shores from later this month.
Chief Health Officer Paul Kelly has moved to ease concerns, stating there is no need for such action in Australia.
"The AstraZeneca COVID-19 vaccine is effective, it is safe, and it's a high-quality vaccine," he said.
Professor Kelly said more than 11 million people had been vaccinated in the UK without evidence of an increase in blood clots.
He said while it was important to carefully monitor any unusual events, these incidents could not necessarily be blamed on vaccines.
Prof Kelly spoke to British and European medicine regulators on Sunday night and stressed those who have halted the vaccine had done so out of an abundance of caution.
He said Australia had strong and clear protocols around reporting adverse reactions.
World Health Organisation spokeswoman Dr Margaret Harris said a link between the vaccine and blood clotting "has not been shown".
The federal government insists the vaccine rollout will be completed by October despite a slow start to the program.
Physician Dr Norman Swan, the face of the ABC's coronavirus coverage, said if the apparent side-effects proved to be significant, it could cause major problems for Australia.
"I think [The Department of Health] are panicking behind the scenes because we've loaded the dice on AstraZeneca vaccine," he told ABC News Breakfast.
"If Astra turns out to be a problem, then we've got very little back-up here in Australia in terms of immunisation."
In addition, Australia has acquired 20 million doses of the Pfizer vaccine.
'Highly unusual' reaction to vaccine
The moves by some of Europe's largest and most populous countries will deepen concerns about the slow roll-out of vaccines in the region, which has been plagued by shortages due to problems producing vaccines including AstraZeneca's.
Austria and Spain have stopped using particular batches and prosecutors in the northern Italian region of Piedmont earlier seized 393,600 doses following the death of a man hours after he was vaccinated.
It was the second region to do so after Sicily, where two people had died shortly after having their shots.
The World Health Organisation earlier on Monday appealed to countries not to suspend vaccinations against a disease that has caused more than 2.7 million deaths worldwide.
"As of today, there is no evidence that the incidents are caused by the vaccine and it is important that vaccination campaigns continue so that we can save lives and stem severe disease from the virus," WHO spokesman Christian Lindmeier said.
The United Kingdom said it had no concerns, while Poland said it thought the benefits outweighed any risks.
The WHO said its advisory panel was reviewing reports related to the vaccine and would release its findings as soon as possible.
But it said it was unlikely to change its recommendations, issued last month, for widespread use including in countries where the South African variant of the virus may reduce its efficacy.
The European Medicines Agency (EMA) has also said there was no indication the events were caused by the vaccination and that the number of reported blood clots was no higher than seen in the general population.
The handful of reported side-effects in Europe have upset vaccination programs already under pressure over slow roll-outs and vaccine scepticism in some countries.
The Netherlands said on Monday it had registered 10 cases of possible noteworthy adverse side-effects from the AstraZeneca vaccine, hours after the government put its vaccination program on hold following reports of potential side-effects in other countries.
Denmark reported "highly unusual" symptoms in a 60-year-old citizen who died from a blood clot after receiving the vaccine, the same phrase used on Saturday by Norway about three people under the age of 50 it said were being treated in hospital.
"It was an unusual course of illness around the death that made the Danish Medicines Agency react," the agency said in a statement late on Sunday.
One of the three health workers hospitalised in Norway after receiving the AstraZeneca shot had died, health authorities said on Monday, but there was no evidence that the vaccine was the cause.
They said they would continue their probe and that no more suspected cases had been reported since Saturday.
AstraZeneca said earlier it had conducted a review covering more than 17 million people vaccinated in the European Union and the UK which had shown no evidence of an increased risk of blood clots.
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