Vaccine safety indicator for the immunization agenda 2030
Extract from GACVS meeting of 1-3 December 2020, published in the WHO Weekly Epidemiological Record of 22 January 2021
At its meeting in December 2014, GACVS proposed that the ratio of 10 reports of adverse events following immunization (AEFI) per 100 000 surviving infants per year be a benchmark for determining whether a country has a functional AEFI surveillance system. This indicator has been the mainstay of AEFI reporting globally as part of the Global Vaccine Action Plan7 monitoring and evaluation framework and has been used as a benchmark to evaluate the progress of vaccine safety performance at national, regional and global levels.
With introduction of the immunization agenda 2030 (IA 20308) and GVSB 2.0,9 which focuses on achieving “a world where everyone, everywhere, at every age, fully benefits from vaccines for good health and well-being”, an indicator is required for monitoring progress in AEFI surveillance in all age groups.
Changes to the existing indicator are therefore being proposed by a working group of GACVS members, external experts, WHO technical units and the WHO Collaborating Centre for International Drug Monitoring:
- It is proposed to introduce a new indicator of the rate of case-based serious AEFI (date of onset in January–December of the previous year) reported per 1 000 000 total population of a country or sub-national area in a year.
- It is proposed that serious AEFI be documented on a reporting form or listed in a line-list with basic information on the patient, reporter, vaccine and event. The United Nations population estimate for the year10 will be used to determine the country population and the denominator. It is proposed that the initial target be at least 1 serious case report per 1 000 000 individuals (of all ages) per year according to the date of onset of the AEFI.
- This benchmark is based on current reporting rates by Member States in different WHO regions and the feasibility of transitioning to the new indicator during the next decade. In alignment with the IA 2030 paradigm, it was considered that the countries might be able to achieve the proposed initial global milestone (1 serious AEFI case report per 1 000 000 population per year) with their current system preparedness and progressively improve to achieve escalated benchmarks during the decade (5 serious AEFI cases per 1 000 000 population per year by 2026 and 10 serious AEFI cases per 1 000 000 population per year by 2030).
- Monitoring the proportion of countries per WHO region that report individual serious AEFI into Vigibase (the WHO global database of individual case safety reports) every year, according to the date of onset of the AEFI, would help to determine whether data are harmonized and shared between the national regulatory agency (NRA) and the national Expanded Programme on Immunization (EPI).
GACVS agreed that case-based reporting rate is a good indicator to aspire for but expressed concern that some LMIC would have difficulty in achieving it, especially initially. GACVS proposed that the new indicator be pilot-tested for feasibility and that the previous practice, of collecting aggregated data, be continued until all countries can report on the new indicator.
Furthermore, as it is challenging to collect case-based information at district level and transmit it to state, provincial and national levels with paper-based tools, electronic tools are preferred, and countries are encouraged to build this capacity.
7 Global vaccine action plan 2011–2020. Geneva: World Health Organization; 2012 (https://www.who.int/teams/immunization-vaccines-and-biologicals/strategies/global-vaccine-action-plan, accessed December 2020).
8 See https://www.who.int/teams/immunization-vaccines-and-biologicals/strategies/ia2030
9 Global vaccine safety blueprint 2.0 (GVSB2.0). Geneva: World Health Organization; 2019 (https://www.who.int/vaccine_safety/gvs_blueprint-consultation/en/, accessed December 2020).