Don’t believe the scaremongers: you’re better off with a second AstraZeneca jab

There are a number of facts that anyone hesitant to get their second AstraZeneca dose should bear in mind.

The AstraZeneca vaccine is now recommended for those over 60 in Australia. Picture: AFP

The changing advice around ­AstraZeneca comes at a time when the vast majority of people who have been vaccinated have received only one shot.

Therein lies the biggest concern around the recommendation that only those aged over 60 should get AstraZeneca.

How many older Australians who have had one shot of AstraZeneca will now have their confidence rocked such that they don’t turn up for their second dose?

That’s the issue looming large for the federal government.

There are a number of facts that anyone hesitant to get their second AstraZeneca dose should bear in mind.

A woman receives the AstraZenca vaccine at the Royal Exhibition Building Covid-19 Vaccination Centre in Melbourne. Picture: Getty Images

Firstly, there have been zero reports of thrombosis with thrombocytopenia – the rare blood-clotting syndrome that is causing concern – following second doses of AstraZeneca in Australia.

That may not reassure some, given the number of people who have received second doses in Australia is very small.

So let’s take some statistics from a country where tens of millions of people have received their second dose of AstraZeneca: Britain. The numbers of TTS in the UK following second doses of AstraZeneca are tiny, much smaller than the already very small risk of blood clots following a first dose. In total, the UK has reported 23 cases of TTS following a second dose of AstraZeneca. That’s out of 15.7 million second doses administered.

It puts the rate of TTS following second doses of AstraZeneca at around one in 1.5 million. That compares with the incidence following a first dose of AstraZeneca at around 14.2 cases per million vaccines given.

So the chances of getting a rare blood-clotting syndrome following a second dose of AstraZeneca is around 20 times less than the already extremely low chance of getting clots following a first dose.

There are good indications that older Australians understand how small these risks are, compared to the much higher chance of severe illness or death from Covid-19. Despite bad publicity for AstraZeneca for months before the first shots of that vaccine ever entered arms, there has been relatively little vaccine hesitancy observed in those aged over 60.

Already, two out of three Australians aged over 60 have received at least one dose of vaccine, and in almost all cases that was AstraZeneca.

“Our message is clear: to those 3.8 million Australians who have had their first dose of AstraZeneca, go and get your second dose,” Health Department secretary Brendan Murphy said on Thursday.

The reasons why the second dose is so important are clear and well-established.

Even though one dose provides some degree of protection as soon as 12 days following immunisation, and efficacy after only one dose may be in the order of 70 per cent, that protection diminishes over several months.

The second dose encourages the body to create stronger protection against the SARS-CoV-2 virus that causes Covid-19.

Given the fact that so many older Australians have turned up in such large numbers for AstraZeneca, despite changing advice and bad publicity, the government will be banking on people making a sensible decision regarding having their second shot.

The protection of our community depends on it.