How the WHO coordinates global adverse event following immunization surveillance
The WHO's Adverse Events Following Immunization (AEFI) surveillance system coordinates global vaccine safety monitoring. Through international collaboration, the WHO helps member states detect, investigate, and respond to vaccine safety signals that may have international implications.
Managed by the Uppsala Monitoring Centre (Sweden), VigiBase contains over 30 million adverse event reports from more than 170 countries. Key features:
WHO classifies AEFIs into 5 categories:
Caused or precipitated by the active component or another component of the vaccine.
Caused by a vaccine that is defective in quality, including its administration device as provided by the manufacturer.
Caused by inappropriate vaccine handling, prescribing, or administration — preventable by nature.
Arising from anxiety about the immunization, not from the vaccine itself. Examples include vasovagal episodes.
Caused by something other than the vaccine or immunization process. Would have occurred regardless of vaccination.
WHO. "Pharmacovigilance." World Health Organization. https://www.who.int/teams/regulation-prequalification/regulation-and-safety/pharmacovigilance
WHO. "AEFI Surveillance Guidelines." World Health Organization. https://www.who.int/publications/i/item/9789241507455
WHO. "Global Advisory Committee on Vaccine Safety (GACVS)." World Health Organization. https://www.who.int/groups/global-advisory-committee-on-vaccine-safety
Uppsala Monitoring Centre. "VigiBase." WHO Collaborating Centre for International Drug Monitoring. https://www.who-umc.org/vigibase/vigibase/