ATAGI reports weekly and their latest report is now out.
ATAGI considered updated estimates of risk of TTS by age group in Australia and note that 20 cases have been confirmed and a further 3 are considered probable in around 1.5 million doses of COVID-19 Vaccine AstraZeneca given up to 5 May 2021. Although estimates of risk based on small numbers of cases are imprecise, the risk of TTS is estimated in Australia at around:
- 2.8 per 100,000 in those <50 years; and
- 1.4 per 100,000 in those ≥50 years.
Of the cases of TTS reported after vaccination with the AstraZeneca COVID-19 Vaccine in Australia, one of these patients had a fatal outcome. All other patients are stable or recovering.
It is difficult to compare rates of TTS with those in other countries due to differences in case definition and assessment, but the rates reported in Australia are broadly similar to those reported in the UK and Europe. However, the cases seen in Australia have presented somewhat differently to those in the UK and Europe, which may reflect the high case ascertainment and early case detection in Australia.
Clinical awareness of TTS is high and suspected cases are rapidly investigated in Australia: this may explain why the majority of Australian cases have recovered or are expected to recover. Notwithstanding this, ATAGI also notes that additional data is needed to understand causal relationship for cases that are under investigation.
An update from the Australian Technical Advisory Group on Immunisation (ATAGI) following their weekly meeting on 19 May 2021.
www.health.gov.au
All confirmed and probable cases of TTS so far (with the exception of the fatality of a 48-year-old woman from NSW) are recovering and stable. The information currently available to the TGA indicates that 21 of the patients are out of hospital, while the two that remain in hospital are responding to treatment and stable.
Information about the TGA's safety monitoring of COVID-19 vaccines
www.tga.gov.au
So with TTS at present in Australia:
- Those now vaccinated with AZ know to look for abdominal pain and/or severe headache that do not settle with pain relief in the period of 4-26 days after vaccination..
- Appropriate treatments are now available
- Now that it is being specifically looked for the number of cases is not surprisingly higher. If you don't look, you do not find the not so serious cases.
- Clinicians also now know to use the platelet test.
- However this also means that people receive treatment in a timely manner
- Since it was realised what was causing TTS including the treatments no deaths have occurred in Australia
With Pfizer this week's discussion included:
Comirnaty (Pfizer) vaccine
Side effects to the Comirnaty vaccine continue to be reported to the TGA and are consistent with what has been observed internationally. This week, describe the reporting of diarrhoea and vomiting as a suspected side effect of the Comirnaty vaccine.
Diarrhoea and vomiting
Diarrhoea and vomiting can occur following vaccination with the Comirnaty vaccine. These adverse events were recently added to the Product Information for Comirnaty based on post-market adverse event data.
Vomiting and diarrhoea have been commonly reported in Australia after vaccination with Comirnaty. To 16 May 2021, the TGA has received 281 reports of diarrhoea and 335 reports of vomiting following vaccination with the Comirnaty vaccine. Of those who reported duration, most said they were better after two days. We have also received around 1000 reports listing nausea as a suspected side effect.
These are expected side effects from this vaccine, and are reasonably common side effects for many medicines and vaccines more broadly. Clinical trials of the Comirnaty vaccine reported just under 3% of people experienced gastrointestinal side effects such as nausea, vomiting, diarrhoea and abdominal pain.