Extract from the meeting of WHO GACVS, published in the WHO Weekly Epidemiological Record of 1st March 2024

GACVS received a briefing on the activities of the Strategic Advisory Group of Experts on Immunization (SAGE) covering a number of viruses and vaccines, including COVID-19, Dengue, Meningococcal Meningitis, and Cholera.

GACVS was updated with the SAGE recommendations on COVID-19 vaccines including the monovalent Omicron XBB vaccines and for optimum use of COVID-19 vaccines.

Updates on the SAGE recommendations on the new Takeda Dengue vaccine (TAK-003) were also provided including the recommendation on post-authorization studies to be conducted to further study vaccine effectiveness and safety against serotypes 3 and 4.

GACVS was also updated with an overview of the SAGE workplan for 2022 to 2025, which has nine active working groups: COVID-19, Dengue, Ebola, Malaria, Meningitis, Polio, Smallpox and Mpox, RSV, and Pneumococcus. Soon to be reactivated is HPV. Other groups and activities include an ad hoc group on Mumps, IA 2023, and AMR. Future working groups being considered are Chikungunya, Cholera, Yellow Fever, Japanese Encephalitis, and Varicella Zoster.

GACVS was also briefed on the progress of developing WHO vaccine reaction rate information sheet on COVID-19 vaccines which was commenced in late 2022. The work achieved thus far includes, synthesizing rates of short-term adverse events for reactogenicity and select causally-related serious adverse events of special interest.

GACVS members commended the progress made to develop the COVID-19 background rate sheets. While the committee agreed with the concept of the sheets and their design, a number of suggestions were made, including to have technical information reviewed by an independent expert and the sheets, generally, also by a communications expert. GACVS suggested to include additional details such as demographic and geographic elements, risks associated with conditions, and qualifying or contextualizing quantitative data.

Full report of WHO GACVS and WHO ACSoMP 13–15 November 2023, published on 1st March 2024

Extract from report of GACVS meeting of 15-16 May 2023, published in the WHO Weekly Epidemiological Record on 11 August 2023

The objectives of the session were to provide updates on discussions from the previous GACVS meeting regarding the use of AEFI monitoring and analysis tools. WHO vaccine reaction rate information sheets1 are a resource to assist with risk communication and investigation of AEFI. Work on information sheets for COVID-19 vaccines commenced in late 2022, undertaken by the National Centre for Immunization Research and Surveillance, Australia, at the request of WHO. To date, results for myocarditis and pericarditis rates following mRNA and protein subunit COVID-19 vaccines have been shared with GACVS. These rates were generated following a rigorous literature review process, with systematic data extraction and synthesis. 

In December 2020, GACVS recommended adopting a new indicator to monitor the performance of national AEFI reporting systems. The new indicator assessed the number of individually reported serious AEFI cases per million total population in a geographic area annually, with at least one serious AEFI case per million population reported into Vigibase (the WHO global database of individual case safety reports), suggestive of a functional AEFI surveillance system. This replaced a previous indicator of at least 10 AEFI cases per 100 000 surviving children per year.

At previous meetings^{3, 4, 5} the GACVS requested that global vaccine pharmacovigilance be strengthened, particularly within the context of the WHO Programme for International Drug Monitoring. Aspects in particular need of attention include prompt data transmission by countries, assurance of data quality, and the processing and analysis of data, including timely signal detection and action. As a result, a GACVS subgroup was formed to work closely with the secretariat to ensure that the initiative continues to move forward in a timely fashion.⁴ A report of the subgroup’s activities and the outcome of its 11 June 2007 meeting were presented to the full Committee. Most of the subgroup meeting was spent reviewing issues raised by the secretariat (emergency response to crises involving adverse events following immunization (AEFI); potential utility of invoking the International Health Regulations (IHR) as a way to facilitate WHO investigation of serious AEFI in different settings; and an initiative to develop a Global Vaccine Safety Datalink project). It was agreed that development of an emergency response protocol should be pursued, but that invoking the IHR to investigate AEFI should probably be employed only in rare and special circumstances; WHO will further deliberate on how this might be implemented before a final decision is made. Enthusiastic support was expressed for WHO participation in the Global Vaccine Safety Datalink project. The inclusion of vaccine pharmacovigilance sessions at 2 international meetings – the 4th Biennial Conference on Signal Detection and Interpretation in Pharmacovigilance (London, UK, 14–15 June 2007) and the 7th International Society of Pharmacovigilance (Bournemouth, UK, 21–24 October 2007) – was also highlighted.

³See No. 28, 2005, pp. 242–247.

⁴See No. 28, 2006 pp. 273–278.

⁵See No 3, 2007, pp. 18–24.

Full report of GACVS meeting of 12-13 June 2007, published in the WHO Weekly Epidemiological Record on 20 July 2007

At previous meetings ^{3, 4}, the GACVS requested that global vaccine pharmacovigilance be strengthened, particularly within the context of the WHO Programme for International Drug Monitoring. Aspects in particular need of attention include data transmission by countries, assurance of data quality, and the processing and analysis of data, including timely signal detection and action. As a result of the above-mentioned request, a subgroup of 6 GACVS members was formed to work closely with the secretariat to ensure that the initiative continues to move forward in a timely fashion4. A report of the subgroup’s activities was presented to the full committee. The specific terms of reference of this subgroup are: to advise WHO regarding the development of a high-quality system for reporting, detecting, analysing and communicating adverse events following immunization (AEFI) at a global level; and to advise WHO, the WHO Collaborating Centre for International Drug Monitoring based in Uppsala, Sweden, (known as the Uppsala Monitoring Centre or UMC) and Member States on specific issues relating to implementing activities aimed at achieving the first goal. To achieve this goal, specific objectives and deliverables have been agreed upon, and these will be undertaken by the subgroup over the next couple of years. A high priority will be to raise the profile and awareness of pharmacovigilance within the immunization community using existing WHO networks and other means.

A report on a visit to Uppsala by representatives of the secretariat and subgroup was presented. Key areas for action include: (i) increasing vaccine-specific expertise at the UMC through the creation of a position dedicated to vaccine safety; (ii) assisting in the recruitment of additional volunteer expert reviewers who can assess potential vaccine safety signals; and (iii) engaging scientific experts to consider what types of methods are best for detecting vaccine safety signals. Deficiencies with respect to vaccines in the anatomical therapeutic chemical and defined daily dose (ATC/DDD) classification and WHO’s Drug Dictionary need to be addressed. A programme of work is planned to review and propose modifications appropriate to vaccines to the ATC/DDD; these proposals will be presented to the WHO Collaborating Centre for Drug Statistics Methodology, Oslo, Norway, at its forthcoming meeting.

³See No. 28, 2005, pp. 242-247

⁴See No. 28, 2006, pp. 273-278

Full report of GACVS meeting of 29-30 November 2006, published in the WHO Weekly Epidemiological Record on 19 January 2007