Independent expert review of recently reported cases of suspected anaphylaxis following the AstraZeneca ChAdOx1-S COVID-19 vaccine has concluded that there is no increased risk of anaphylaxis associated with the vaccine above the expected rate for any other vaccine. Anaphylaxis is a very rare side effect that can occur with any vaccine.
The Therapeutic Goods Administration (TGA) convened a meeting of experts drawn from the TGA's Advisory Committee on Vaccines and the Australian Technical Advisory Group on Immunisation to review the individual cases in detail. The panel included medical experts in vaccine safety, infectious diseases, immunology, epidemiology and social science.
On Thursday 18 March 2021, the panel reviewed the five reports and information on two additional cases of suspected anaphylaxis following the AstraZeneca COVID-19 vaccine received by the TGA. Four reports came from Queensland and one from each of Victoria, NSW and Northern Territory.
The panel found that the information in only one of the reports met the required assessment criteria for anaphylaxis. This individual made a full recovery.
In considering the reports, the panel used the internationally-accepted Brighton Collaboration case definition of anaphylaxis. The Brighton Collaboration provides widely recognised methods for monitoring the safety of vaccines, developed by a group of global experts.
The panel advised that some of these cases may have represented allergic reactions or immediate stress responses to vaccination that may appear similar to an anaphylactic reaction, with symptoms such as nausea, throat tightness or rapid heart rate. Although they might not meet the criteria for anaphylaxis, they still need to be monitored and taken seriously.
In addition to the advice provided below in the statement published on 17 March 2021, which is still relevant and applicable, the TGA recommends that immunisation providers continue to provide adrenaline where they feel it is clinically required.
