Question Number: 157
PDR Number: SQ22-000135
Date Submitted: 24/02/2022
Department or Body: Department of Health
Question 83
Prior to provisionally approving the COVID-19 vaccines, the Therapeutic Goods Administration (TGA) conducted a thorough assessment of the data which includes clinical studies, non-clinical and toxicology studies, as well as chemistry and manufacturing information. The vaccines were provisionally approved because they meet Australia’s high standards for quality, safety and effectiveness.
Reporting of over 100,000 adverse events to the TGA does not indicate that the COVID-19 vaccines are unsafe. Reporting of an adverse event following vaccination to the TGA does not mean that the vaccine caused the event. The TGA encourages health professionals and consumers to report adverse events following immunisation, even if there is only a small chance that the vaccine caused the event.
Under state and territory regulations in New South Wales, Western Australia, Queensland, Northern Territory and the Australian Capital Territory, it is mandatory for health professionals to report all adverse events following immunisation. The high reporting rate for COVID-19 vaccines is a result of the TGA’s activities to promote and facilitate adverse event reporting to support robust safety monitoring, and the intense public interest in the COVID-19 vaccines. Many adverse events reported following administration of a vaccine are simply coincidental and due to other causes, not the vaccine itself.
A large proportion of the adverse events following COVID-19 vaccination reported to the TGA describe expected vaccine side effects (numbers detailed to 20 February 2022), such as headache (29,000 reports), muscle pain (18,000 reports), fever (16,000 reports), tiredness (14,000 reports) and nausea (14,000 reports). In clinical trials these side effects were generally of mild to moderate intensity and resolved within a few days.
Post-marketing surveillance has identified some potentially serious side effects associated with COVID-19 vaccines, such as:
- Thrombosis with thrombocytopenia (TTS), which is a rare clotting disorder that may occur after the AstraZeneca vaccine, and in Australia has been reported in two out of every 100,000 people after a first dose and 0.3 out of every 100,000 people after a second dose. In Australia, the risk of dying from TTS after vaccination is about one in a million.
- Guillain-Barre Syndrome, which is a rare immune disorder affecting the nerves that can result in pain, numbness, muscle weakness and difficulty walking, and has been reported in about one in every 100,000 people following any dose of the AstraZeneca vaccine. Guillain-Barre Syndrome has also been associated with infections, including COVID-19, and it is expected that some of the reports of this syndrome submitted to the TGA have other causes and are part of the natural background rate of this condition.
- Myocarditis, or heart inflammation, which has been reported in one to two people in every 100,000 doses of the Pfizer or Moderna vaccines. Myocarditis may also be related to infections. Most cases reported following vaccination are mild and resolve following treatment and rest.
Since the beginning of the vaccine roll-out to 27 February 2022, about 54 million doses of COVID-19 vaccines have been given in Australia. The TGA has identified 11 reports where the cause of death was linked to vaccination.
Question 84
At the time of Professor Skerritt’s interview with John Laws in June 2021, over 5 million doses had been administered in Australia so there was very extensive clinical experience with safety.
Post-market monitoring and ongoing studies are continuing to gather data on the safety and effectiveness of the COVID-19 vaccines. Since vaccination with COVID-19 vaccines began in early December 2020, just under 11 billion vaccine doses have been administered worldwide, which has allowed extremely rare side effects to be identified through post-market monitoring, such as those described in the response to question 83.
Clinical trials for any new medicine or vaccine may not detect all possible side effects because they do not include enough patients to detect those adverse events that occur very rarely. TGA and other regulatory agencies around the world monitor the safety of medicines and vaccines to contribute to a better understanding of their safety when they are used outside the controlled conditions of clinical trials.
Question 85
Please see response to questions 29-31, SQ22-000105.