Thrombosis with thrombocytopenia syndrome (TTS) following AstraZeneca COVID-19 vaccine

AstraZeneca COVID-19 vaccine Vaxzevria is associated with a very rare risk of a condition called thrombosis with thrombocytopenia syndrome, or TTS. 

TTS involves blood clots (thrombosis) along with low platelet levels (thrombocytopenia), and occurs around 4-28 days after vaccination. It is currently estimated to affect around 6 people per million doses. To date, almost all reported cases were after the first dose of the vaccine. 

Several resources are available to provide information to immunisation providers about TTS following vaccination with COVID-19 Vaccine AstraZeneca.

NCIRS COVID-19 vaccines: Frequently asked questions

We have answered commonly asked questions about thrombosis with thrombocytopenia syndrome following COVID-19 Vaccine AstraZeneca on our COVID-19 vaccines: Frequently asked questions webpage. Access these and other questions and answers about COVID-19 vaccines here.

ATAGI statements and advices

• ATAGI reinforce recommendations on use of COVID-19 vaccines following review of vaccine safety data and benefits - 23 April 2021
• Information for immunisation providers on thrombosis with thrombocytopenia syndrome (TTS) following COVID-19 vaccination
• ATAGI immunisation provider guide to obtaining informed consent for COVID-19 vaccine
• Consent form for COVID-19 vaccination
• ATAGI clinical guidance on COVID-19 vaccine in Australia in 2021

Australian Government Department of Health resources

• About the AstraZeneca COVID-19 vaccine
• Information on COVID-19 AstraZeneca vaccine
• Preparing for COVID-19 vaccination
• After your AstraZeneca vaccine
• Patient information sheet on AstraZeneca COVID-19 vaccine and thrombosis with thrombocytopenia syndrome (TTS)
• Weighing up the potential benefits against risk of harm from COVID-19 Vaccine AstraZeneca

Therapeutic Goods Administration advisories 

• TGA additional Australian cases of TTS likely linked to vaccine 23 April 2021
• TGA AstraZeneca ChAdOx1-S COVID-19 vaccine updated safety advisory 9 April 2021

Others

• THANZ advisory statement 24 April 2021
• THANZ ELISA and functional testing request form
• Brighton Collaboration Interim Case Definition of Thrombosis with Thrombocytopenia Syndrome (TTS) v9.2
• Guidance from the Expert Haematology Panel (EHP) on Covid-19 Vaccine-induced Immune Thrombocytopenia and Thrombosis (VITT) 20 April 2021
• EMA AstraZeneca’s COVID-19 vaccine 14 April 2021
• WHO GAVCS review 16 April 2021
• EMA PRAC meeting highlights 9 April 2021