A batch of a vaccine against Hepatitis B may not have worked, leading health experts to issue a warning that patients treated with the drugs may need to be revaccinated.
Patients treated with the Engerix B vaccine (batch no.AHBV591BB) between Monday March 9 and Monday April 6 should be inoculated again.
Experts at the Medicines and Healthcare products Regulatory Agency (MHRA) said the drugs, which were frozen during transportation, were not unsafe, but they may be ineffective.
MHRA chief executive Professor Kent Woods said: ‘The MHRA has contacted healthcare professionals and requested them to contact all patients who have been vaccinated with this batch and invite them to be revaccinated.’
As an added precaution, the MHRA is asking patients to check whether they received a vaccine from this batch by contacting the GP or travel clinic which administered it.
Families of overseas travellers who may have been affected should also contact the clinic where they were inoculated to ensure they have not been affected.