Shaping Vaccine Safety Evidence Across Europe

DSRU colleagues have contributed to a major VAC4EU study examining thrombosis with thrombocytopaenia syndrome (TTS) — a rare blood clotting condition — following the Oxford-AstraZeneca COVID-19 vaccine. The findings are published in Vaccine.

The UK arm of the study drew on CPRD Aurum, the UK’s database of anonymised primary care records. Across the UK, Spain and the Netherlands, the study included more than 5.3 million people who received the AstraZeneca vaccine.

What the study found

The findings suggest a possible increased risk of TTS after vaccination, particularly:

• After the first dose
• In people aged under 60
• Within 1–42 days after vaccination

Results varied between countries and data sources — underlining why collaborative, real-world evidence matters in vaccine safety monitoring.

We're proud to contribute to this important European collaboration.

Forns J, Pajouheshnia R, Aurelius T, et al. Risk of thrombosis with thrombocytopaenia syndrome (TTS) after vaccination with AZD1222: a European VAC4EU post-authorisation safety study. Vaccine. 2026;86:128723. doi:10.1016/j.vaccine.2026.128723

https://www.sciencedirect.com/science/article/pii/S0264410X26005323?dgcid=coauthor