Improving global monitoring of vaccine safety: a survey of national centres participating in the WHO Programme for International Drug Monitoring.

Background: The WHO Programme for International Drug Monitoring (PIDM) was established in 1968 following the thalidomide disaster. The PIDM has had considerable success in analyzing drug-related adverse event reports, but more limited progress has been made in analyzing vaccine-related reports. In June 2005, the Global Advisory Committee on Vaccine Safety, acknowledging these limitations, called for a global consultation to address the need for improved monitoring and analysis of vaccine-related adverse event reports on an international level.

Objective: In preparation for this consultation and as part of a larger study designed to evaluate the PIDM, a survey of the National Pharmacovigilance Centres of all 76 countries participating in the PIDM at the time the survey was conducted.

Results: Thirty-six countries (47%) responded. Of the 36 responding countries, 16 (44%) reported having a separate surveillance system for adverse events following immunizations (AEFIs) and 30 (83%) reported forwarding AEFI reports to the PIDM. Seven of the 36 countries (19%) indicated that one or more population subgroups are systematically excluded from their country's AEFI surveillance system. Five of the seven countries exclude reports concerning recipients of travellers' vaccines; three exclude recipients of vaccines administered by private physicians outside the national immunization programme and supply scheme; and five exclude reports from the military sector. Only half of the respondents knew of the Brighton Collaboration, a major international initiative aimed at the standardization of AEFI definitions.

Conclusion: The survey identified critical elements that should be addressed quickly to improve global vaccine safety monitoring. Communication between national adverse drug reaction and AEFI surveillance authorities, ability to pay for advancing technology in developing countries, and proper use of services and terminologies are issues of concern.