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Coronavirus: Vaccination

Answer

Vaccines are only authorised once they have met robust standards of effectiveness, safety, and quality set by the independent medicines’ regulator, the Medicines and Healthcare products Regulatory Agency (MHRA).

The monitoring of vaccine safety does not stop once a vaccine has been approved. The MHRA continuously monitors safety data from a range of sources to ensure that the benefits continue to outweigh any risks. This includes reports of adverse events and rare side effects retrieved from the MHRA’s Yellow Card Database, interim and final study reports for clinical trials, post-authorisation safety studies, and data from scientific literature. A dedicated team of assessors reviews this information on a weekly basis to look for safety issues or unexpected, rare events.

The Department also commissions research through the National Institute for Health and Care Research (NIHR) and continues to welcome funding applications for research into any aspect of human health, including for vaccine side effects.

Since the start of the pandemic, the NIHR has allocated more than £110 million of funding for COVID-19 vaccine research, including consideration of issues around vaccine safety. As part of this, the Department commissioned a £1.6 million programme of work through the NIHR to understand the mechanisms underlying the occurrence of COVID-19 vaccine-induced thrombotic thrombocytopenia syndrome, a rare condition of blood clotting with low platelets following vaccination for COVID-19. This research was published in July 2025 and is available in the NIHR Journals Library.

Secondary information

Type

Written question

Reference

88866

Session

2024-26

Grouped for answer

Yes

Subjects

Research Coronavirus Vaccination Side effects AstraZeneca

Link

View this Written question on www.parliament.uk