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If your child is 1 to 5 years old and lives in Barry, or goes to a nursery, school or childcare setting in Barry, you can get a free hepatitis A vaccine.

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Vaccine resources for health and social care professionals - Vaccine safety

Contraindications and special considerations

Adverse events following immunisation

Vaccines induce protection by eliciting active immune responses to specific antigens. There may be predictable adverse reactions (side effects): most are mild and resolve quickly. However, it is not always possible to predict individuals who might have a mild or serious reaction to a vaccine.

Following guidance on contraindications will ensure the risk of serious adverse effects is minimised. For more information about vaccines offered in Wales and the diseases they help protect against, visit the list of vaccinations for health and social care professionals page.

Reporting vaccine safety issues

The Yellow Card Scheme is vital in helping the Medicines and Healthcare products Regulatory Agency (MHRA) monitor the safety of vaccines in the UK. All serious suspected adverse drug reactions (ADRs) for established medicines and vaccines should be reported, even if the effect is well recognised. Causality does not have to be proved to report a suspected ADR, only a suspicion is needed.

For urgent issues related to a suspected defect in a vaccine the MHRA Defective Medicines Reporting Centre, contact MHRA (external site). 

The public and healthcare professionals can find further information on the work of the MHRA agency, safety warnings, and how to report any problems at the UK Government website (external site). 

Patient Safety Wales supports NHS organisations to improve patient safety (external site). 

The World Health Organisation (WHO) (external site) register of reliable validated websites which can be recommended to parents and professionals. 

The Vaccine Safety Net (external site) is a global network of websites, established by the World Health Organization, that provides reliable information on vaccine safety. 

Vaccine alerts

The latest MHRA safety warnings, alerts and recalls can be found at the UK government website (external site). 

Black triangle scheme

New vaccines that are under additional monitoring have an inverted black triangle symbol (▼) displayed in their package leaflet and summary of product characteristic, together with a short sentence explaining what the triangle means – it does not mean the vaccine is unsafe. All suspected ADRs for these vaccines should be reported. Find information on the Black Triangle Scheme (external site).

Surveillance and monitoring for vaccine safety

Surveillance and monitoring for vaccine safety on the green book, chapter 9 (external site). 

Vaccination surveillance information can be found at:

Vaccine damage payment scheme

Vaccine Damage Payment Scheme on the green book, chapter 10 (external site). 

The Vaccine Damage Payment Scheme (external site) provides a single, tax-free payment to people (or their families) who have suffered severe mental and/or physical disablement as a result of immunisation against certain diseases. 

Page last reviewed: 21st August 2026