Impacts of Rift Valley Fever virus: a One Health approach to assess burden and inform prevention and control options

Background: Rift Valley Fever (RVF) is a climate-sensitive emerging zoonotic disease associated with large-scale livestock production losses and human disease burden in Sub-Saharan Africa and the Middle East. While recognized as a key One Health issue based on its transmission dynamics involving human, animal and environmental determinants, there has been poor coordination between sectors to reduce the risk and impact of RVF. Efforts to counter the disease remain largely reactive, presenting an ongoing threat to local and global health security. The intent of this dissertation was to improve understanding of the burden of RVF across society and to identify entry points for practical and cost-effective interventions at global, national, and local scales. Methods: For Aim 1, we quantified global impacts using official and unofficial reports of human and animal disease and deaths from RVF. We assessed univariate correlation between RVF reporting and broad country-level predictor variables for African nations and describe country development characteristics as well as review major capacity and implementation gaps. In Aim 2, we conducted the first national cost analysis for RVF in South Africa, utilizing a One Health approach to combine data from multiple sectors (agriculture, health, environment, tourism, and finance) and identify the type, magnitude, and distribution of expenditures and losses in outbreaks and inter-epidemic periods between 2003-2018. Aim 3 focuses on actionable policy recommendations, using a survey on RVF prevention and control practices and willingness to pay (WTP) measures to improve understanding of economic behaviors of farm owners, the primary decision-maker for RVF vaccine uptake, in South Africa’s Free State and Northern Cape provinces. Results: In Aim 1, we find that a total of 5,228 suspected human cases and 987 deaths, and 72,960 animal cases and 17,810 deaths, were officially reported in 32 countries between 2000-2019. Of the twelve country-level predictor variables assessed, a higher number of RVF publications was significantly associated with higher odds of official reporting of RVF 2000-2019 (OR=1.5), whereas higher level of political stability and absence of violence was protective against RVF reporting (OR=.39), as was higher percentage of population with access to electricity (OR=.97) (all p\u3c.05). On average, countries reporting RVF in Africa have high dependence on livestock, and face major economic, infrastructure, and capacity deficits, which can be expected to affect implementation and efficacy of RVF prevention, detection and response campaign. In Aim 2, we find that between 2003-2018, RVF was associated with at least US$120.6 million in expenditures and losses in South Africa. The majority of impacts were incurred during epidemic periods. The burden of disease from RVF was estimated at 680.913 Disability-Adjusted Life Years, with the majority from premature death. Productivity losses and medical and public health spending accounted for approximately 5$727.23 per year. Higher mean WTP to avoid animal losses from RVF was significantly associated with higher number of domestic animals and wool farming (p\u3c.05). There was also a significant difference in WTP to vaccinate herds against RVFbased on level of risk of RVF circulating in mosquitoes in their province or farm (p\u3c.000). Most farms indicated they would take measures other than or in addition to vaccination if they thought risk of RVF was high in their province, including insecticide/dip (90.65%) and antibiotics (28.04%). Several barriers and enablers were identified for uptake of livestock vaccination against RVF. Among the barriers, approximately half the farms thought vaccine supply was sufficient in general, whereas less than one-fourth thought it was sufficient during an outbreak. Discussion: Over the past two decades, RVF has affected multiple continents. The lack of a comprehensive reporting system for animal and human disease burden makes tracking official estimates challenging. A comparison to published estimates suggests wide under-reporting of RVF. In terms of prevention and control practices, affected countries face several major economic, capacity, and infrastructure barriers that may affect uptake and effectiveness of vaccination. Encouragingly, from our national- and farm-level analyses in South Africa, we find that there is some existing investment in RVF in interepidemic periods, and that there may be supply and demand-side practices that may be supported by low-cost or multi-disease interventions, such as enhanced risk communication and tracking of vaccine availability. Our findings can be paired with further willingness to pay studies of other payer groups to identify optimal resource allocation options. Future macro- and micro-costing studies can improve precision of data inputs. While the need for a One Health approach has been articulated for improved understanding of the risks of RVF, our findings demonstrate how a One Health lens also has utility in assessing impacts to identify a broader range of affected stakeholders and inform coordinated action to address both animal and human disease and wider societal impacts

Climate Change and Health: Transcending Silos to Find Solutions

Background: Climate change has myriad implications for the health of humans, our ecosystems, and the ecological processes that sustain them. Projections of rising greenhouse gas emissions suggest increasing direct and indirect burden of infectious and noninfectious disease, effects on food and water security, and other societal disruptions. As the effects of climate change cannot be isolated from social and ecological determinants of disease that will mitigate or exacerbate forecasted health outcomes, multidisciplinary collaboration is critically needed. / Objectives: The aim of this article was to review the links between climate change and its upstream drivers (ie, processes leading to greenhouse gas emissions) and health outcomes, and identify existing opportunities to leverage more integrated global health and climate actions to prevent, prepare for, and respond to anthropogenic pressures. / Methods: We conducted a literature review of current and projected health outcomes associated with climate change, drawing on findings and our collective expertise to review opportunities for adaptation and mitigation across disciplines. / Findings: Health outcomes related to climate change affect a wide range of stakeholders, providing ready collaborative opportunities for interventions, which can be differentiated by addressing the upstream drivers leading to climate change or the downstream effects of climate change itself. / Conclusions: Although health professionals are challenged with risks from climate change and its drivers, the adverse health outcomes cannot be resolved by the public health community alone. A phase change in global health is needed to move from a passive responder in partnership with other societal sectors to drive innovative alternatives. It is essential for global health to step outside of its traditional boundaries to engage with other stakeholders to develop policy and practical solutions to mitigate disease burden of climate change and its drivers; this will also yield compound benefits that help address other health, environmental, and societal challenges

One Health proof of concept: Bringing a transdisciplinary approach to surveillance for zoonotic viruses at the human-wild animal interface.

As the world continues to react and respond inefficiently to emerging infectious diseases, such as Middle Eastern Respiratory Syndrome and the Ebola and Zika viruses, a growing transdisciplinary community has called for a more proactive and holistic approach to prevention and preparedness - One Health. Such an approach presents important opportunities to reduce the impact of disease emergence events and also to mitigate future emergence through improved cross-sectoral coordination. In an attempt to provide proof of concept of the utility of the One Health approach, the US Agency for International Development's PREDICT project consortium designed and implemented a targeted, risk-based surveillance strategy based not on humans as sentinels of disease but on detecting viruses early, at their source, where intervention strategies can be implemented before there is opportunity for spillover and spread in people or food animals. Here, we share One Health approaches used by consortium members to illustrate the potential for successful One Health outcomes that can be achieved through collaborative, transdisciplinary partnerships. PREDICT's collaboration with partners around the world on strengthening local capacity to detect hundreds of viruses in wild animals, coupled with a series of cutting-edge virological and analytical activities, have significantly improved our baseline knowledge on the zoonotic pool of viruses and the risk of exposure to people. Further testament to the success of the project's One Health approach and the work of its team of dedicated One Health professionals are the resulting 90 peer-reviewed, scientific publications in under 5 years that improve our understanding of zoonoses and the factors influencing their emergence. The findings are assisting in global health improvements, including surveillance science, diagnostic technologies, understanding of viral evolution, and ecological driver identification. Through its One Health leadership and multi-disciplinary partnerships, PREDICT has forged new networks of professionals from the human, animal, and environmental health sectors to promote global health, improving our understanding of viral disease spillover from wildlife and implementing strategies for preventing and controlling emerging disease threats

Checklist for One Health epidemiological reporting of evidence (COHERE)

One Health is defined as the intersection and integration of knowledge regarding humans, animals, and the environment, yet as the One Health scientific literature expands, there is considerable heterogeneity of approach and quality of reporting in One Health studies. In addition, many researchers who publish such studies do not include or integrate data from all three domains of human, animal, and environmental health. This points to a critical need to unify guidelines for One Health studies. This report details the Checklist for One Health Epidemiological Reporting of Evidence (COHERE) to guide the design and publication format of future One Health studies. COHERE was developed by a core writing team and international expert review group that represents multiple disciplines, including human medicine, veterinary medicine, public health, allied professionals, clinical laboratory science, epidemiology, the social sciences, ecohealth and environmental health. The twin aims of the COHERE standards are to 1) improve the quality of reporting of observational or interventional epidemiological studies that collect and integrate data from humans, animals and/or vectors, and their environments; and 2) promote the concept that One Health studies should integrate knowledge from these three domains. The 19 standards in the COHERE checklist address descriptions of human populations, animal populations, environmental assessment, spatial and temporal relationships of data from the three domains, integration of analyses and interpretation, and inclusion of expertise in the research team from disciplines related to human health, animal health, and environmental health

Global avian influenza surveillance in wild birds: A strategy to capture viral diversity

Wild birds play a major role in the evolution, maintenance, and spread of avian influenza viruses. However, surveillance for these viruses in wild birds is sporadic, geographically biased, and often limited to the last outbreak virus. To identify opportunities to optimize wild bird surveillance for understanding viral diversity, we reviewed responses to a World Organisation for Animal Health-administered survey, government reports to this organization, articles on Web of Knowledge, and the Influenza Research Database. At least 119 countries conducted avian influenza virus surveillance in wild birds during 2008-2013, but coordination and standardization was lacking among surveillance efforts, and most focused on limited subsets of influenza viruses. Given high financial and public health burdens of recent avian influenza outbreaks, we call for sustained, cost-effective investments in locations with high avian influenza diversity in wild birds and efforts to promote standardized sampling, testing, and reporting methods, including full-genome sequencing. (Résumé d'auteur