Building capacity for active surveillance of vaccine adverse events in the Americas: A hospital-based multi-country network

Strategies and interventions to strengthen pharmacovigilance systems in low-income and middle-income countries: a scoping review

OBJECTIVES

The slow progress of pharmacovigilance (PV) in low-income and middle-income countries (LMIC) raises questions about core challenges on the growth of PV, and the appropriateness of strategies used so far to develop PV. Therefore, this scoping review aims to describe strategies and interventions to strengthen PV in LMIC and to propose recommendations for future investments in PV capacity building.

INCLUSION CRITERIA

Publications included were primary studies, articles, policy and guideline papers, describing interventions to strengthen PV in LMIC.

METHODS

The review was conducted following the Joanna Briggs Institute (JBI) guidelines on conducting scoping reviews. Literature searches were performed in MEDLINE, EMBASE, Web of Science, PDQ-evidence, CINAHL and other relevant websites from January 1990 to January 2021. Two reviewers independently screened titles, abstracts and full texts. One reviewer performed data extraction and descriptive analysis, which were reviewed by two other reviewers.

RESULTS

10 922 unique titles were screened and 152 were eligible for full text review. Of these, 57 and an additional 13 reports from grey literature fulfilled eligibility criteria for inclusion in the review. These were grouped into two categories: (1) Interventions aimed at increasing PV knowledge and adverse drug reactions (ADR) reporting (45 papers), primarily education of healthcare professionals (HCP), alone or in combination with other interventions such as mobile and electronic reporting and (2) Interventions aimed at strengthening various components of the national PV system (25 papers), describing strategies or mixed interventions implemented at the national level, targeting different components of the national PV system.

CONCLUSIONS

Results of this review suggest that educating HCP on ADR reporting is the most common approach to build PV capacity in LMIC. Though important, education alone is insufficient and should ideally be organised within the holistic framework of strengthening national PV systems, with a focus on also building capacity for advanced activities such as signal detection.

Advancing sustainable development goals through immunization: a literature review

BACKGROUND

Immunization directly impacts health (SDG3) and brings a contribution to 14 out of the 17 Sustainable Development Goals (SDGs), such as ending poverty, reducing hunger, and reducing inequalities. Therefore, immunization is recognized to play a central role in reaching the SDGs, especially in low- and middle-income countries (LMICs). Despite continuous interventions to strengthen immunization systems and to adequately respond to emergency immunization during epidemics, the immunization-related indicators for SDG3 lag behind in sub-Saharan Africa. Especially taking into account the current Covid19 pandemic, the current performance on the connected SDGs is both a cause and a result of this.

METHODS

We conduct a literature review through a keyword search strategy complemented with handpicking and snowballing from earlier reviews. After title and abstract screening, we conducted a qualitative analysis of key insights and categorized them according to showing the impact of immunization on SDGs, sustainability challenges, and model-based solutions to these challenges.

RESULTS

We reveal the leveraging mechanisms triggered by immunization and position them vis-à-vis the SDGs, within the framework of Public Health and Planetary Health. Several challenges for sustainable control of vaccine-preventable diseases are identified: access to immunization services, global vaccine availability to LMICs, context-dependent vaccine effectiveness, safe and affordable vaccines, local/regional vaccine production, public-private partnerships, and immunization capacity/capability building. Model-based approaches that support SDG-promoting interventions concerning immunization systems are analyzed in light of the strategic priorities of the Immunization Agenda 2030.

CONCLUSIONS

In general terms, it can be concluded that relevant future research requires (i) design for system resilience, (ii) transdisciplinary modeling, (iii) connecting interventions in immunization with SDG outcomes, (iv) designing interventions and their implementation simultaneously, (v) offering tailored solutions, and (vi) model coordination and integration of services and partnerships. The research and health community is called upon to join forces to activate existing knowledge, generate new insights and develop decision-supporting tools for Low-and Middle-Income Countries' health authorities and communities to leverage immunization in its transformational role toward successfully meeting the SDGs in 2030.

Comparative effectiveness of influenza vaccines among U.S. Medicare beneficiaries ages 65 years and older during the 2019-20 season

BACKGROUND

Around 50,000 influenza-associated deaths occur annually in the U.S., overwhelmingly among individuals ages >65 years. Although vaccination is the primary prevention tool, investigations have shown low vaccine effectiveness (VE) in recent years, particularly among the elderly. We analyzed the relative VE (RVE) of all influenza vaccines among Medicare beneficiaries ages >65 years to prevent influenza hospital encounters during the 2019-20 season.

METHODS

Retrospective cohort study using Poisson regression and inverse probability of treatment weighting (IPTW). Exposures included egg-based high-dose trivalent (HD-IIV3), egg-based adjuvanted trivalent (aIIV3), egg-based standard dose (SD) quadrivalent (IIV4), cell-based SD quadrivalent (cIIV4), and recombinant quadrivalent (RIV4) influenza vaccines.

RESULTS

We studied 12.7 million vaccinated beneficiaries. Following IPTW, cohorts were well balanced for all covariates and health-seeking behavior indicators. In the adjusted analysis, RIV4 (RVE 13.3%, 95% CI 7.4%, 18.9%), aIIV3 (RVE 8.2%, 95% CI 4.2%, 12.0%), and HD-IIV3 (RVE 6.8%, 95% CI 3.3%, 10.1%) were significantly more effective in preventing hospital encounters than the reference egg-based SD IIV4, while cIIV4 was not significantly more effective than IIV4 (RVE 2.8%, 95% CI -2.8%, 8.2%). Our results were consistent across all analyses.

CONCLUSIONS

In this influenza B-Victoria and A(H1N1)-dominated season, RIV4 was moderately more effective than other vaccines, while the HD-IIV3 and aIIV3 were more effective than the IIV4 vaccines, highlighting the contributions of antigen amount and adjuvant use to VE. Egg adaptation likely did not substantially affect our RVE evaluation. Our findings, specific to the 2019-20 season, should be evaluated in other studies using virological case confirmation.

Two decades of vaccine innovations for global public good: Report of the Developing Countries' Vaccine Manufacturers Network 20th meeting, 21-23 october 2019, Rio de Janeiro, Brazil

The Developing Countries' Vaccine Manufacturers Network, joined by global health organizations, held its 20th meeting celebrating two decades of vaccine innovations for global public good. Health leaders from industry, academia and global health organizations reviewed efforts to accelerate innovation, improve access to vaccines, overcome inequalities and strengthen technological and public-health management capabilities. Discussion topics included World Health Organization's immunization strategy, Pan American Health Organization's system-strengthening efforts, Gavi's evaluation of vaccine coverage in middle income countries and developments on public-market intelligence. Health market trends, delivery gaps, integration of system-wide needs, costs and benefits, and implications for stakeholder decision-making were areas of focus. Novel thinking was discussed on integration of policy, financing, regulatory pathways and alignment of innovation priorities to improve efficiency in vaccine development pathways. The Vaccine Innovation Prioritization Strategy collaboration presented nine global innovation priorities, and many other partners and members presented updates on their priorities. Novel technologies and platforms, such as RNA-based vaccines, adenoviral vectors, bioconjugation, blow-fill-seal and two-dimensional barcodes, provided opportunities to accelerate vaccine innovations. Challenges in planning and operations at global level included those in health security, polio eradication, re-emergence of diseases, disparities between forecasts and orders and heterogeneous regulatory requirements. Manufacturers were urged to accelerate innovation and prequalification of high-impact vaccines, such as pneumococcal, human papillomavirus and rotavirus vaccines, to strengthen immunization globally.

Active surveillance of acute paediatric hospitalisations demonstrates the impact of vaccination programmes and informs vaccine policy in Canada and Australia

Sentinel surveillance of acute hospitalisations in response to infectious disease emergencies such as the 2009 influenza A(H1N1)pdm09 pandemic is well described, but recognition of its potential to supplement routine public health surveillance and provide scalability for emergency responses has been limited. We summarise the achievements of two national paediatric hospital surveillance networks relevant to vaccine programmes and emerging infectious diseases in Canada (Canadian Immunization Monitoring Program Active; IMPACT from 1991) and Australia (Paediatric Active Enhanced Disease Surveillance; PAEDS from 2007) and discuss opportunities and challenges in applying their model to other contexts. Both networks were established to enhance capacity to measure vaccine preventable disease burden, vaccine programme impact, and safety, with their scope occasionally being increased with emerging infectious diseases’ surveillance. Their active surveillance has increased data accuracy and utility for syndromic conditions (e.g. encephalitis), pathogen-specific diseases (e.g. pertussis, rotavirus, influenza), and adverse events following immunisation (e.g. febrile seizure), enabled correlation of biological specimens with clinical context and supported responses to emerging infections (e.g. pandemic influenza, parechovirus, COVID-19). The demonstrated long-term value of continuous, rather than incident-related, operation of these networks in strengthening routine surveillance, bridging research gaps, and providing scalable public health response, supports their applicability to other countries.

Enhancing global vaccine pharmacovigilance: Proof-of-concept study on aseptic meningitis and immune thrombocytopenic purpura following measles-mumps containing vaccination

New vaccines designed to prevent diseases endemic in low and middle-income countries (LMICs) are now being introduced without prior record of utilization in countries with robust pharmacovigilance systems. To address this deficit, our objective was to demonstrate feasibility of an international hospital-based network for the assessment of potential epidemiological associations between serious and rare adverse events and vaccines in any setting. This was done through a proof-of-concept evaluation of the risk of immune thrombocytopenic purpura (ITP) and aseptic meningitis (AM) following administration of the first dose of measles-mumps-containing vaccines using the self-controlled risk interval method in the primary analysis. The World Health Organization (WHO) selected 26 sentinel sites (49 hospitals) distributed in 16 countries of the six WHO regions. Incidence rate ratios (IRR) of 5.0 (95% CI: 2.5-9.7) for ITP following first dose of measles-containing vaccinations, and of 10.9 (95% CI: 4.2-27.8) for AM following mumps-containing vaccinations were found. The strain-specific analyses showed significantly elevated ITP risk for measles vaccines containing Schwarz (IRR: 20.7; 95% CI: 2.7-157.6), Edmonston-Zagreb (IRR: 11.1; 95% CI: 1.4-90.3), and Enders'Edmonston (IRR: 8.5; 95% CI: 1.9-38.1) strains. A significantly elevated AM risk for vaccines containing the Leningrad-Zagreb mumps strain (IRR: 10.8; 95% CI: 1.3-87.4) was also found. This proof-of-concept study has shown, for the first time, that an international hospital-based network for the investigation of rare vaccine adverse events, using common standardized procedures and with high participation of LMICs, is feasible, can produce reliable results, and has the potential to characterize differences in risk between vaccine strains. The completion of this network by adding large reference hospitals, particularly from tropical countries, and the systematic WHO-led implementation of this approach, should permit the rapid post-marketing evaluation of safety signals for serious and rare adverse events for new and existing vaccines in all settings, including LMICs.