Suspensions follow reports that some people developed blood clots after receiving the shot, but WHO says no proven link.
Thailand has launched an inoculation campaign with AstraZeneca’s COVID-19 shot and Australia announced it has no plans to stop administering the jab, despite a growing number of European nations suspending the vaccine’s use amid concerns over safety.
Thai Prime Minster Prayuth Chan-ocha on Tuesday became the first person to receive the AstraZeneca vaccine in the Southeast Asian nation, saying he was doing so “to boost confidence for the general public”.
Prayuth and other cabinet members had initially been due to get their vaccine shots on Friday but Thailand temporarily suspended the use of the AstraZeneca vaccine amid reports from Europe that it could cause dangerous blood clots.
Several European countries – including Germany, France, Italy and Spain – have since halted the use of the shot as a “precautionary” measure, although the British drugmaker and international regulators say there is no evidence to suggest the vaccine caused the clots.
Venezuela and Indonesia have also suspended the use of the AstraZeneca jab.
On Sunday, AstraZeneca said it reviewed data from more than 17 million people vaccinated in the United Kingdom and the European Union and found 37 cases of blood clots.
It said none of the cases was proven to have been caused by the vaccine and that the incidence of clots was much lower than would be expected to occur naturally in a general population of such a size and was similar to that of other licenced COVID-19 vaccines.
The World Health Organization (WHO) and the EU’s European Medicines Agency (EMA) backed that assessment, prompting Thailand to announce it would begin using the AstraZeneca vaccine.
In addition to the Thai prime minister, 15 cabinet ministers also received the AstraZeneca jab on Tuesday. They were injected with some of the 117,300 doses that Thailand imported for emergency use earlier this month.
The country plans to make the AstraZeneca vaccine domestically and begin its mass inoculation campaign in June when the Thai-produced jab becomes available.
In Australia, Treasurer Josh Frydenberg told broadcaster Sky News on Tuesday the government “will continue to proceed with the rollout of AstraZeneca”.
Australia launched its nationwide immunisation drive last month, much later than many other countries and began first vaccinations using the AstraZeneca vaccine last week.
The majority of the country’s 25 million people will be inoculated with the AstraZeneca jab and authorities have secured nearly 54 million doses, with 50 million to be produced locally from the end of March.
The UK, which has doled out 11 million doses of the AstraZeneca jab, and Canada, which approved the vaccine in February, also say they plan to stick with the jab.
The AstraZeneca product is just one of several vaccines being deployed across the world to fight the coronavirus pandemic but it is a key pillar of a United Nations-backed project known as COVAX that aims to supply COVID-19 vaccines to the world’s poorer countries.
The programme began shipments in late February and has plans to ship more than 200 million doses by the end of May – nearly all of them versions of the AstraZeneca vaccine.
A total of 92 countries are to receive vaccines for free through COVAX, which is led by the WHO; Gavi, a vaccine group; and the Coalition for Epidemic Preparedness Innovations. A further 90 countries and eight territories have agreed to pay for doses through the programme.
Tedros Adhanom Ghebreyesus, WHO’s director-general, said on Monday that the global health body’s advisory committee on vaccine safety had been reviewing the available data and would meet on Tuesday.
The decision of some European nations to suspend the use of AstraZeneca does not mean the incidence of blood clots are linked to vaccination, he said, stressing that it was routine practice to investigate such cases.
“The greatest threat that most countries face now is lack of access to vaccines,” he said.
Dr Soumya Swaminathan, the WHO’s chief scientist, noted that 300 million doses of coronavirus vaccines had been injected around the world and there was no documented death linked to any one of them.
She said the rates at which blood clots have occurred in people who received the AstraZeneca vaccine “are in fact less than what you would expect in the general population”.
She added: “We do not want people to panic and we would, for the time being, recommend that countries continue vaccinating with AstraZeneca.”
The EMA, which has called a meeting for Thursday to review experts’ findings on the AstraZeneca shot, also said the incidence of blood clots in vaccinated people “seems not to be higher than that seen in the general population”.
The agency said that while the investigation is going on, “the benefits of the AstraZeneca vaccine in preventing COVID-19, with its associated risk of hospitalisation and death, outweigh the risks of side effects.”