evidence: After a vaccine is approved for use, regulators conduct robust effectiveness monitoring as well as monitoring of safety and risk minimisation activities (pharmacovigilance). They need to continuously monitor vaccine safety to ensure that the benefits of the vaccine continue to outweigh the risks. Regulators do this by: [...] Regulators, often in collaboration with public health authorities, can take decisive action if a safety issue is identified. These actions can include issuing safety communications for patients, healthcare professionals and the community; updating the product information or consumer information for the vaccine; preventing the release of a particular batch of vaccine; and, taking other regulatory actions such as restriction of vaccine authorisation to a particular subgroup of the community or revocation of authorisation. Regulators approve and maintain an approval of a vaccine only if they determine that the known and potential benefits of the vaccine outweigh its known and potential risks.