More than 10K reports across 1.5 million doses

The TGA is “closely monitoring” adverse events related to COVID-19 vaccines, finding a rate of three cases of rare clotting syndrome per million doses

There have been 10,619 adverse events reported across 1,586,252 doses of COVID-19 vaccines administered in Australia, according to the TGA’s latest report up to 18 April.

This equates to a reporting rate of 6.7 adverse events per 1000 doses.

The AstraZeneca COVID-19 vaccine’s most frequently reported adverse events to 11 April were expected vaccine side effects such as headache, fever, muscle pain, chills and fatigue.

Adverse events of special interest reported for the AstraZeneca COVID-19 vaccine include anaphylaxis (48 reports), bleeding disorder (47 reports), seizure (19 reports), loss of sense of taste or smell (10 reports), low platelets (five reports), facial weakness (four reports), liver injury (three reports).

Assessment of reports against the accepted case definition for anaphylaxis indicates a rate of less than 10 reports per million doses of the AstraZeneca COVID-19 vaccine.

The overall number of reports of blood clots in the veins or arteries for the AstraZeneca vaccine is no higher than the expected background rate for the more common type of blood clots in Australia.

These can occur in around 50 Australians every day, separate to vaccination.

While there has been an increase in cases of blood clots submitted to the TGA, this appears to be due to reporting of coincidental blood clots unrelated to vaccination, “due to increased awareness of investigations into a rare and unusual clotting syndrome involving thrombosis (blood clots) with thrombocytopenia (low blood platelet count) following the AstraZeneca COVID-19 vaccine,” said the TGA.

“We are carefully reviewing any Australian reports of possible blood clots following vaccination with the AstraZeneca COVID-19 vaccine to identify any further possible cases of this disorder to better characterise this potential risk, which is now referred to as ‘thrombosis with thrombocytopenia syndrome’ (TTS),” it said.

The total number of TTS cases reviewed by the independent expert Vaccine Safety Investigation Group and likely to be linked to vaccination is three, as of 16 April 2021.

Based on this, the reported rate of TTS in Australia is approximately three per million doses (from 926,424 doses to 16 April 2021).

The reported rate in the UK, where more than 20 million doses of the vaccine have been given, is approximately five reports per million doses.

Healthcare professionals have been asked to be alert to the signs and symptoms of thromboembolism and thrombocytopenia as well as coagulopathies.

“Vaccinated individuals should be instructed to seek immediate medical attention if they develop symptoms such as a severe or persistent headache, blurred vision, shortness of breath, chest pain, leg swelling, persistent abdominal pain or unusual skin bruising and/or petechia a few days after vaccination,” said the TGA.

Meanwhile there have been five reports of low platelets up to 11 April 2021.

Two of these have been associated with thrombosis and confirmed as TTS cases as previously discussed.

The number of reports of low platelets overall is no higher than the expected background rate in Australia.

Up to 11 April, the most frequently reported adverse events for the Pfizer vaccine were headache, muscle pain, nausea, fever and fatigue.

These were side effects commonly reported in clinical trials.

Meanwhile adverse events of special interest reported for the Pfizer vaccine include 45 reports of anaphylaxis, 15 reports of bleeding disorder, 10 reports of facial weakness, 10 reports of seizure, seven reports of loss of sense of taste or smell, and three reports of a cardiac event.

There have been no reports of deaths associated with suspected anaphylaxis, and experts have determined that while many cases reported as anaphylaxis may appear similar to an anaphylactic reaction, they do not meet the accepted case definition.

The TGA estimates a rate of 35 cases of anaphylaxis per million doses of the Pfizer vaccine, although it is undertaking further assessment and states this rate may be an “overestimate”.

It reminds healthcare practitioners: “Routine vaccination procedures include keeping people under observation for 15 minutes after vaccination and having appropriate medical treatment on hand so that anaphylaxis can be rapidly managed, if it occurs.

“A second dose of [the Pfizer vaccine] should not be given to those who have experienced anaphylaxis to the first dose.”

The overall number of reports received of bleeding and blood clot disorders, such as stroke, pulmonary embolism and deep vein thrombosis for the Pfizer vaccine is no higher than the expected background rate for the more common type of blood clots in Australia.

Reported events are not related to the very rare clotting disorder associated with very low platelets being investigated in relation to the AstraZeneca COVID-19 vaccine, said the TGA.

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  1. Sergio Kas

    Your rate of blood clots seem low. This says Denmarks rate of blood clots is 1 in 40,000. Norway says its rate of blood clots is 1 in 25,000
    And the EMA at its press conference said the rate is 1 to 2 per 100,000, so upto 1 in 50,000.

    • Russell Smith

      So – what is the real point here? Is it that reports to the TGA are limited by the relatively small number of injections here vs Europe? Such that the sample size and therefore the local experience is lacking? Or is it that side-effects are present but which have neither been reported to and by TGA yet? Interesting that TGA/others keep trying to put up stats that say 50ppl per day have a stroke – in comparison to the injections – but not that the risk is actually IN ADDITION to that background rate.

      • Sergio Kas

        Yes, this is also interesting. 62 cases of Myocarditis or heart inflamation after the Pfizer shot, and 2 deaths in people under 30.

        • Jarrod McMaugh

          Sergio, I think it’s worth noting that all medicines – including vaccines – have adverse events, which can and does include death in many cases

          The figures you are quoting aren’t (unfortunately) unusual.

          This data isn’t hidden, but the majority of people have no idea of the nature of adverse events of treatments…. but also of not treating a condition.

          It is always a matter of weighing up risk vs benefit. This is always considered for the individual, and in many cases of public health, it is considered for the broader population as well.

          People think medicines and vaccines are “100% safe” – this isn’t true, and they aren’t represented like this

          People think that side effects etc are hidden from people – this isn’t true either, as this information is available publicly.

          • Sergio Kas

            Side effects are seldom reported in our media “protect the vaccination program”
            and are they hidden? I dont know, but I do know that there is massive under-reporting as this article in Canadian medical journal shows.

   The 4th paragraph down says there is up to 96% under-reporting of “Serious” side effects. I know vaccines have different reporting systems, but it is all the same doctors, am I to believe they are 96% better with vaccine side effects?
            And it is even worse in the US, I have the data if you want it.

          • Jarrod McMaugh

            The data is readily available; thankyou though – underreporting of side effects (and benefits, btw) is a common issue that is well understood.

            Underreporting is affected by many things; in many cases, the person affected doesn’t report their side effects….. and this may be because they didn’t realise it was a side effect; the side effect may have been physiological in nature without any signs that they would recognise (like a change in kidney function or liver function);

            health professionals also underreport those they observe; but the majority of underreporting of side effects are caused by those side effects not being detected or recognised.

            This is the same with most health interventions.

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