BACK

UK Yellow Card reporting on COVID-19 vaccines published by the MHRA, including updated numbers of CVST and other thrombosis events with low platelets

This article was published on
April 22, 2021

This explainer is more than 90 days old. Some of the information might be out of date or no longer relevant. Browse our homepage for up to date content or request information about a specific topic from our team of scientists.

The latest weekly summary of Yellow Card reporting has been published by the Medicines & Healthcare products Regulatory Agency (MHRA), and includes updated numbers of Cerebral Venous Sinus Thrombosis (CVST) and other thrombosis events with low blood platelets (thrombocytopenia).

The latest weekly summary of Yellow Card reporting has been published by the Medicines & Healthcare products Regulatory Agency (MHRA), and includes updated numbers of Cerebral Venous Sinus Thrombosis (CVST) and other thrombosis events with low blood platelets (thrombocytopenia).

Publication

What our experts say

Context and background

Resources

Media briefing

Media Release

Expert Comments: 

Prof Adam Finn

The weekly update from the MHRA reports more cases of TTS (Thrombotic thrombocytopenic syndrome) following the Oxford-AstraZeneca vaccine, as expected. There is now a very high level of awareness of this syndrome amongst the public and clinicians throughout the country and cases are being reported reliably and quickly but there are also cases that occurred previously now being recognised and reported as well. MHRA are using a very clearly defined case definition to ensure consistency. In other words they are making sure that the cases being reported are really this syndrome and not something else.  This can take some time and while there is uncertainty, unconfirmed cases are designated possible or probable. I would expect the true number of cases per million doses of vaccine to become clear fairly soon as these reports stabilise but it is already clear that it is going to remain a very rare event.  There remains an urgent need to understand the mechanism underlying these cases, to monitor and optimise rapid diagnosis and treatment and, if possible, to identify risk factors all of which might improve outcomes and enable cases to be prevented.

Q&A

No items found.