Global challenges in preparedness and response to epidemic infectious diseases

Nipah virus disease: what can we do to improve patient care?

The year 2023 marked the 25th anniversary of the first detected outbreak of Nipah virus disease. Despite Nipah virus being a priority pathogen in the WHO Research and Development blueprint, the disease it causes still carries high mortality, unchanged since the first reported outbreaks. Although candidate vaccines for Nipah virus disease exist, developing new therapeutics has been underinvested. Nipah virus disease illustrates the typical market failure of medicine development for a high-consequence pathogen. The unpredictability of outbreaks and low number of infections affecting populations in low-income countries does not make an attractive business case for developing treatments for Nipah virus disease-a situation compounded by methodological challenges in clinical trial design. Nipah virus therapeutics development is not motivated by commercial interest. Therefore, we propose a regionally led, patient-centred, and public health-centred, end-to-end framework that articulates a public health vision and a roadmap for research, development, manufacturing, and access towards the goal of improving patient outcomes. This framework includes co-creating a regulatory-compliant, clinically meaningful, and context-specific clinical development plan and establishing quality standards in clinical care and research capabilities at sites where the disease occurs. The success of this approach will be measured by the availability and accessibility of improved Nipah virus treatments in affected communities and reduced mortality.

An mRNA technology transfer programme and economic sustainability in health care

The World Health Organization (WHO) set up the messenger ribonucleic acid (mRNA) technology transfer programme in June 2021 with a development hub in South Africa and 15 partner vaccine producers in middle-income countries. The goal was to support the sustainable development of and access to life-saving vaccines for people in these countries as a means to enhance epidemic preparedness and global public health. This initiative aims to build resilience and strengthen local vaccine research, and development and manufacturing capacity in different regions of the world, especially those areas that could not access coronavirus disease 2019 (COVID-19) vaccines in a timely way. This paper outlines the current global vaccine market and summarizes the findings of a case study on the mRNA technology transfer programme conducted from November 2022 to May 2023. The study was guided by the vision of the WHO Council on the Economics of Health for All to build an economy for health using its four work streams of value, finance, innovation and capacity. Based on the findings of the study, we offer a mission-oriented policy framework to support the mRNA technology transfer programme as a pilot for transformative change towards an ecosystem for health innovation for the common good. Parts of this vision have already been incorporated into the governance of the mRNA technology transfer programme, while other aspects, especially the common good approach, still need to be applied to achieve the goals of the programme.

Financing for pandemic preparedness and response measures: a systematic scoping review

Objective

To obtain insights into reducing the shortfall in financing for pandemic preparedness and response measures, and reducing the risk of another pandemic with social and economic costs comparable to those of the coronavirus disease.

Methods

We conducted a systematic scoping review using the databases ScienceDirect, Scopus, JSTOR, PubMed® and EconLit. We included articles published in any language until 1 August 2023, and excluded grey literature and publications on epidemics. We categorized eligible studies according to the elements of a framework proposed by the World Health Organization Council on the Economy of Health for All: (i) root/structural causes; (ii) social position/foundations; (iii) infrastructure and systems; and (iv) communities, households and individuals.

Findings

Of the 188 initially identified articles, we included 60 in our review. Most (53/60) were published after 2020, when academic interest had shifted towards global financing mechanisms. Most (37/60) addressed two or more of the council framework elements. The most frequently addressed element was infrastructure and systems (54/60), discussing topics such as health systems, financial markets and innovation ecosystems. The roots/structural causes were discussed in 25 articles; communities, households and individuals in 22 articles; and social positions/foundations in 11.

Conclusion

Our review identified three important gaps: a formal definition of pandemic preparedness and response, impeding the accurate quantification of the financing shortfall; research on the extent to which financing for pandemic preparedness and response has been targeted at the most vulnerable households; and an analysis of specific financial instruments and an evaluation of the feasibility of their implementation.

Pharmacokinetic Analyses of a Lipid Nanoparticle-Encapsulated mRNA-Encoded Antibody against Rift Valley Fever Virus

Rift Valley fever virus (RVFV) could cause an emergency illness characterized by fever, muscle pain, and even death in humans or ruminants. However, there are no approved antiviral drugs that prevent or treat RVFV infection. While therapeutic antibodies have shown promising potential for prevention or treatment in several studies, many studies are ongoing, especially in the field of infectious diseases. Among these studies, the mRNA-LNP platform shows great potential for application, following the COVID-19 pandemic. Previously, we have obtained a neutralizing antibody against RVFV, which was named A38 protein and verified to have a high binding and neutralization ability. In this study, we aimed to identify an effectively optimized sequence and expressed the prioritized mRNA-encoded antibody in vitro. Notably, we effectively expressed mRNA-encoded protein and used the mRNA-LNP platform to generate A38-mRNA-LNP. Pharmacokinetic experiments were conducted in vivo and set up in two groups of mRNA-A38 group and A38 protein group, which were derived from mRNA-LNP and plasmid DNA-expressed proteins, respectively. A38-mRNA-LNPs were administrated by intramuscular injection, A38 proteins were administrated by intravenous administration, and their unique ability to maintain long-lasting protein concentrations by mRNA-encoded protein was demonstrated with the mRNA-encoded protein providing a longer circulating half-life compared to injection of the free A38 protein. These preclinical data on the mRNA-encoded antibody highlighted its potential to prevent infectious diseases in the future.

From private incentives to public health need: rethinking research and development for pandemic preparedness

Pandemic preparedness and response have relied primarily on market dynamics to drive development and availability of new health products. Building on calls for transformation, we propose a new value proposition that instead prioritises equity from the research and development (R&D) stage and that strengthens capacity to control outbreaks when and where they occur. Key elements include regional R&D hubs free to adapt well established technology platforms, and independent clinical trials networks working with researchers, regulators, and health authorities to better study questions of comparative benefit and real-world efficacy. Realising these changes requires a shift in emphasis: from pandemic response to outbreak control, from one-size-fits-all economies of scale to R&D and manufacture for local need, from de novo product development to last-mile innovation through adaptation of existing technologies, and from proprietary, competitive R&D to open science and financing for the common good that supports collective management and sharing of technology and know-how.

The Future of Epidemic and Pandemic Vaccines to Serve Global Public Health Needs

This Review initiates a wide-ranging discussion over 2023 by selecting and exploring core themes to be investigated more deeply in papers submitted to the Vaccines Special Issue on the "Future of Epidemic and Pandemic Vaccines to Serve Global Public Health Needs". To tackle the SARS-CoV-2 pandemic, an acceleration of vaccine development across different technology platforms resulted in the emergency use authorization of multiple vaccines in less than a year. Despite this record speed, many limitations surfaced including unequal access to products and technologies, regulatory hurdles, restrictions on the flow of intellectual property needed to develop and manufacture vaccines, clinical trials challenges, development of vaccines that did not curtail or prevent transmission, unsustainable strategies for dealing with variants, and the distorted allocation of funding to favour dominant companies in affluent countries. Key to future epidemic and pandemic responses will be sustainable, global-public-health-driven vaccine development and manufacturing based on equitable access to platform technologies, decentralised and localised innovation, and multiple developers and manufacturers, especially in low- and middle-income countries (LMICs). There is talk of flexible, modular pandemic preparedness, of technology access pools based on non-exclusive global licensing agreements in exchange for fair compensation, of WHO-supported vaccine technology transfer hubs and spokes, and of the creation of vaccine prototypes ready for phase I/II trials, etc. However, all these concepts face extraordinary challenges shaped by current commercial incentives, the unwillingness of pharmaceutical companies and governments to share intellectual property and know-how, the precariousness of building capacity based solely on COVID-19 vaccines, the focus on large-scale manufacturing capacity rather than small-scale rapid-response innovation to stop outbreaks when and where they occur, and the inability of many resource-limited countries to afford next-generation vaccines for their national vaccine programmes. Once the current high subsidies are gone and interest has waned, sustaining vaccine innovation and manufacturing capability in interpandemic periods will require equitable access to vaccine innovation and manufacturing capabilities in all regions of the world based on many vaccines, not just "pandemic vaccines". Public and philanthropic investments will need to leverage enforceable commitments to share vaccines and critical technology so that countries everywhere can establish and scale up vaccine development and manufacturing capability. This will only happen if we question all prior assumptions and learn the lessons offered by the current pandemic. We invite submissions to the special issue, which we hope will help guide the world towards a global vaccine research, development, and manufacturing ecosystem that better balances and integrates scientific, clinical trial, regulatory, and commercial interests and puts global public health needs first.

Breakthrough treatments for Ebola virus disease, but no access-what went wrong, and how can we do better?

Three years since proving effective for Ebola virus disease in a clinical trial, two breakthrough treatments are registered and stockpiled in the USA but still not registered and generally available in the countries most affected by this deadly infection of epidemic potential. Analysing the reasons for this, we see a fragmentation of the research and development value chain, with different stakeholders taking on different steps of the research and development process, without the public health-focused leadership needed to ensure the end goal of equitable access in countries where Ebola virus disease is prevalent. Current financial incentives for companies to overcome market failures and engage in epidemic-prone diseases are geared towards registration and stockpiling in the USA, without responsibility to provide access where and when needed. Ebola virus disease is the case in point, but not unique-a situation seen again for mpox and likely to occur again for other epidemics primarily affecting disempowered communities. Stronger leadership in African countries will help drive drug development efforts for diseases that primarily affect their communities, and ensure all partners align with and commit to an end-to-end approach to pharmaceutical development and manufacturing that puts equitable access when and where needed at its core.

The outbreak of Ebola virus disease in 2022: A spotlight on a re-emerging global health menace

Ebola virus disease (EVD) is a rare but highly contagious and lethal disease that occurs predominantly in African countries, with a case-fatality rate of 30-90%. The causative viral pathogens of EVD are within the genus Ebolavirus in the family Filoviridae. The primary route of human-to-human transmission is through direct contact with blood, bodily fluids and secretions from infected individuals. Direct contact with virally contaminated objects and sexual transmission have also been reported. Management of EVD is aggressive supportive care with possibly new therapeutic options. On 20 September 2022, an EVD outbreak was declared in Uganda, caused by Sudan ebolavirus. As of 7 November 2022, a total of 136 confirmed cases, 53 confirmed deaths have been reported, including 18 cases with seven deaths among healthcare workers. In the Democratic Republic of Congo (DRC), an EVD outbreak was also declared on 22 August 2022 (which ended on 27 September 2022); with only one case, a middle-aged woman. At the time when most countries in the world have been occupied with the coronavirus disease 2019 (COVID-19) pandemic and the recent human monkeypox outbreak, these two outbreaks of EVD have the potential to significantly add to the burden on global health. Authorities need to augment their multi-faceted response, including stringent contact tracing and border control, to avoid the catastrophe of the 2014-2016 EVD epidemic.

Amplified effect of social vulnerability on health inequality regarding COVID-19 mortality in the USA: the mediating role of vaccination allocation

Background

Vaccination reduces the overall burden of COVID-19, while its allocation procedure may introduce additional health inequality, since populations characterized with certain social vulnerabilities have received less vaccination and been affected more by COVID-19. We used structural equation modeling to quantitatively evaluate the extent to which vaccination disparity would amplify health inequality, where it functioned as a mediator in the effect pathways from social vulnerabilities to COVID-19 mortality.

Methods

We used USA nationwide county (n = 3112, 99% of the total) level data during 2021 in an ecological study design. Theme-specific rankings of social vulnerability index published by CDC (latest data of 2018, including socioeconomic status, household composition & disability, minority status & language, and housing type & transportation) were the exposure variables. Vaccination coverage rate (VCR) during 2021 published by CDC was the mediator variable, while COVID-19 case fatality rate (CFR) during 2021 published by John Hopkinson University, the outcome variable.

Results

Greater vulnerabilities in socioeconomic status, household composition & disability, and minority status & language were inversely associated with VCR, together explaining 11.3% of the variance of VCR. Greater vulnerabilities in socioeconomic status and household composition & disability were positively associated with CFR, while VCR was inversely associated with CFR, together explaining 10.4% of the variance of CFR. Our mediation analysis, based on the mid-year data (30^th June 2021), found that 37.6% (mediation/total effect, 0.0014/0.0037), 10% (0.0003/0.0030) and 100% (0.0005/0.0005) of the effects in the pathways involving socioeconomic status, household composition & disability and minority status & language, respectively, were mediated by VCR. As a whole, the mediation effect significantly counted for 30.6% of COVID-19 CFR disparity. Such a mediation effect was seen throughout 2021, with proportions ranging from 12 to 32%.

Conclusions

Allocation of COVID-19 vaccination in the USA during 2021 led to additional inequality with respect to COVID-19 mortality. Viable public health interventions should be taken to guarantee an equitable deployment of healthcare recourses across different population groups.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-14592-w.