PREZODE is a global One Health initiative, involving scientists, communities, governments and practitioners, to prevent zoonotic epidemics and pandemics.

Vaccination is considered as the main tool for the Global Control and Eradication Strategy for peste des petits ruminants (PPR), and the efficacity of the PPR-vaccine in conferring long-life immunity has been established. Despite this, previous studies asserted that vaccination can be expensive and consequently, the effectiveness of disease control may not necessarily translate to overall profit for farmers. Also, the consequences of PPR control on socioeconomic indicators like food and nutrition security at a macro-national level have not been explored thoroughly. Therefore, this study seeks to assess ex-ante the impact of PPR control strategies on farm-level profitability and the socioeconomic consequences concerning food and nutrition security at a national level in Senegal. A bi-level system dynamics model, compartmentalised into five modules consisting of integrated production-epidemiological, economics, disease control, marketing, and policy modules, was developed with the STELLA Architect software, validated, and simulated for 30 years at a weekly timestep. The model was parameterised with data from household surveys from pastoral areas in Northern Senegal and relevant existing data. Nine vaccination scenarios were examined considering different vaccination parameters (vaccination coverage, vaccine wastage, and the provision of government subsidies). The findings indicate that compared to a no-vaccination scenario, all the vaccination scenarios for both 26.5% (actual vaccination coverage) and 70% (expected vaccination coverage) resulted in statistically significant differences in the gross margin earnings and the potential per capita consumption for the supply of mutton and goat meat. At the prevailing vaccination coverage (with or without the provision of government subsidies), farm households will earn an average gross margin of $69.43 (annually) more than without vaccination, and the average per capita consumption for mutton and goat meat will increase by 1.13kg/person/year. When the vaccination coverage is increased to the prescribed threshold for PPR eradication (i.e., 70%), with or without the provision of government subsidies, the average gross margin earnings would be $72.23 annually and the per capita consumption will increase by 1.23kg/person/year compared to the baseline (without vaccination). This study's findings offer an empirical justification for a sustainable approach to PPR eradication. The information on the socioeconomic benefits of vaccination can be promoted via sensitization campaigns to stimulate farmers' uptake of the practice. This study can inform investment in PPR control.

The One Health approach calls for collaboration across various sectors and different scales to improve understanding of complex health issues. Regarding epidemiological surveillance, this implies the development of integrated systems that link several surveillance components operating in different domains (human, domestic animals, environment) and involving several actor networks. However, surveillance continues to operate in a very compartmentalized way, with little interaction between sectoral institutions and with the community for the governance and operation of surveillance activities. This is partly explained by the insufficient consideration of the local context and the late involvement of national stakeholders when developing programmes that aimed at strengthening the integration of surveillance. In low- and middle-income countries in particular, there is a strong influence of external partners on the development of intersectoral programmes, including surveillance systems. In this context, we developed and implemented a participatory planning process to support stakeholders of the surveillance system of anthrax in Burkina Faso, in the definition of the One Health surveillance system they wish for and of the pathway to reach it. The workshop produced an action plan that reflects the views and perspectives of representatives of the different categories of stakeholders and beneficiaries of surveillance. In addition, the participation of stakeholders in this participatory co-construction process has also improved their knowledge and mutual understanding, fostering a climate of trust conducive to further collaboration for surveillance activities. However, the quality of the participation raises some questions over the results, and contextual factors may have influenced the process. This underlines the need to include a monitoring and evaluation plan in the process to assess its implementation and ability to produce One Health surveillance modalities that are appropriate, accepted and applied over the long term.

Background Anthrax is a zoonotic disease that causes frequent outbreaks in livestock and fatal human cases in Burkina Faso. Effective surveillance of this disease calls for the establishment of an integrated surveillance system, in line with the One Health concept. However, despite a strong technical and financial support from international partners, surveillance is still poorly conducted within an integrated approach. Based on stakeholder perspectives, the study has for objective to deepen our understanding of the anthrax surveillance system and to identify the obstacles and levers towards a more integrated approach to anthrax surveillance in Burkina Faso. Methods The data was collected from a literature review and interviews with surveillance stakeholders. We first conducted a qualitative descriptive analysis of the data to characterize the surveillance system (programmes, actors, collaboration). In a second step, we conducted a thematic analysis of the informants' discourse in order to identify what represents an obstacle or, conversely, a lever for a more integrated approach to anthrax surveillance. Results The surveillance system of anthrax in Burkina Faso includes three programmes (in the livestock, wildlife and human sectors), which involves 30 actors. These sectoral programmes operate almost independently from one another, although some collaborations are existing for the governance and implementation of surveillance activities. Analysis of the discourse of key stakeholders led to the identification of four categories of factors that may influence the implementation of an integrated surveillance system in the country: knowledge; technical, organizational and social capacities; motivation; intersectoral governance. Conclusions This study highlights the difficulty of translating One Health governance to the national level and the need to better articulate the visions of all categories of stakeholders. This study also reveals the need to develop specific evaluation systems for integrated policies in order to provide credible evidence of their added value for a better management of zoonotic diseases. Finally, our study underlines the need to act upstream the emergence of zoonoses and allocate more resources to the prevention of zoonoses than to their control.

The past two decades have seen an accumulation of theoretical and empirical evidence for the interlinkages between human health and well-being, biodiversity and ecosystem services, and agriculture. The COVID-19 pandemic has highlighted the devastating impacts that an emerging pathogen, of animal origin, can have on human societies and economies. A number of scholars have called for the wider adoption of “One Healthintegrated approaches” to better prevent, and respond to, the threats of emerging zoonotic diseases. However, there are theoretical and practical challenges that have precluded the full development and practical implementation of this approach. Whilst integrated approaches to health are increasingly adopting a social-ecological system framework (SES), the lack of clarity in framing the key concept of resilience in health contexts remains a major barrier to its implementation by scientists and practitioners. We propose an operational framework, based on a transdisciplinary definition of Socio-Ecological System Health (SESH) that explicitly links health and ecosystem management with the resilience of SES, and the adaptive capacity of the actors and agents within SES, to prevent and cope with emerging health and environmental risks. We focus on agricultural transitions that play a critical role in disease emergence and biodiversity conservation, to illustrate the proposed participatory framework to frame and co-design SESH interventions. Finally, we highlight critical changes that are needed from researchers, policy makers and donors, in order to engage communities and other stakeholders involved in the management of their own health and that of the underpinning ecosystems.

Depuis le debut des annees 2000, des propositions de formalisation avec DEVS et ses extensions des systemes multi-agents ont ete proposees. Cet expose se propose de visiter les plus emblematiques d'entre-elles en les restituant dans le contexte de leur developpement, c'est-a-dire en essayant d'identifier a quels types de problemes elles se proposent de repondre et quels sont les apports et les limites de ces propositions. Nous essayerons ensuite de faire une synthese de ces propositions afin de discuter des developpements a venir, notamment dans les domaines de la verification et de la communication des SMAs.

Le reseau DEVS (RED) organise la troisieme edition de son workshop, renomme Journees Francophones de la Modelisation et de la Simulation (JFMS), largement ouvert a la communaute SMA cette annee. RED a pour but de developper, federer et promouvoir les travaux autour de la theorie de la modelisation et de la simulation (TM&S), et plus particulierement autour du formalisme DEVS et de ses extensions. L’objectif est de promouvoir une approche systemique et integree de la modelisation des systemes complexes. Les principaux themes du reseau sont : • l’utilisation de methodes formelles, comme DEVS pour aider a la reproductibilite des experiences de simulation ; • l’ingenierie des modeles ; • la validation et la certification des simulateurs ; • la performance des simulateurs ; • la validation et la verification des modeles.

ObjectiveTo better understand the potential risks of Nipah virus emergence in Cambodia by studying different components of the interface between humans and bats. Methods From 2012 to 2016, we conducted a study at two sites in Kandal and Battambang provinces where fruit bats (Pteropus lylei) roost. We combined research on: bat ecology (reproductive phenology, population dynamics and diet); human practices and perceptions (ethnographic research and a knowledge, attitude and practice study); and Nipah virus circulation in bat and human populations (virus monitoring in bat urine and anti-Nipah-virus antibody detection in human serum). Findings Our results confirmed circulation of Nipah virus in fruit bats (28 of 3930 urine samples positive by polymerase chain reaction testing). We identified clear potential routes for virus transmission to humans through local practices, including fruit consumed by bats and harvested by humans when Nipah virus is circulating, and palm juice production. Nevertheless, in the serological survey of 418 potentially exposed people, none of them were seropositive to Nipah virus. Differences in agricultural practices among the regions where Nipah virus has emerged may explain the situation in Cambodia and point to actions to limit the risks of virus transmission to humans. Conclusion Human practices are key to understanding transmission risks associated with emerging infectious diseases. Social science disciplines such as anthropology need to be integrated in health programmes targeting emerging infectious diseases. As bats are hosts of major zoonotic pathogens, such integrated studies would likely also help to reduce the risk of emergence of other bat-borne diseases.

Dengue is a national priority disease in Cambodia. The Cambodian National Dengue Surveillance System is based on passive surveillance of dengue-like inpatients reported by public hospitals and on a sentinel, pediatric hospital-based active surveillance system. This system works well to assess trends but the sensitivity of the early warning and time-lag to usefully inform hospitals can be improved. During The ECOnomic development, ECOsystem MOdifications, and emerging infectious diseases Risk Evaluation (ECOMORE) project's knowledge translation platforms, Cambodian hospital staff requested an early warning tool to prepare for major outbreaks. Our objective was therefore to find adapted tools to improve the early warning system and preparedness. Dengue data was provided by the National Dengue Control Program (NDCP) and are routinely obtained through passive surveillance. The data were analyzed at the provincial level for eight Cambodian provinces during 2008-2015. The R surveillance package was used for the analysis. We evaluated the effectiveness of Bayesian algorithms to detect outbreaks using count data series, comparing the current count to an expected distribution obtained from observations of past years. The analyses bore on 78,759 patients with dengue-like syndromes. The algorithm maximizing sensitivity and specificity for the detection of major dengue outbreaks was selected in each province. The overall sensitivity and specificity were 73% and 97%, respectively, for the detection of significant outbreaks during 2008-2015. Depending on the province, sensitivity and specificity ranged from 50% to 100% and 75% to 100%, respectively. The final algorithm meets clinicians' and decisionmakers' needs, is cost-free and is easy to implement at the provincial level.

We have presented an approach to ensuring pathways client data validity and improving the design of associated health information infrastructure for community-based coordination of care. Beyond making explicit the aspects in which data quality can fall short, the approach has been shown to inform the design of decision support systems for community health workers and other participants in the Pathways Community HUB. We exploited the existence of pathways structures to organize the data using formal systems concepts to develop an approach that is both well-defined and applicable to support general standards for certification of such organizations. The presentation showed that pathways structures are an important principle not only for organizing the activities of coordination of care but also for structuring the data stored in electronic health records in the conduct of such care. We also showed how it encourages design of effective decision support systems for coordinated care and suggested how interested organizations can set about acquiring such systems.

Despite existence of human vaccines, Japanese Encephalitis (JE) remains a prominent public health problem in Southeast Asia (SEA). JE is caused by a Flavivirus which is transmitted between pigs, the main amplifying hosts, by Culex mosquito bites. Therefore, sow vaccination, pig herd management and vector control –or a combination of these three potential control measures, might constitute additional control measures contributing to reduce JE health impact in humans, and economic losses in pig farms. We built a deterministic metapopulation model, combining a pig and a Culex mosquito vector population, to represent JE virus (JEV) transmission dynamic within a pig herd. The dynamic of the epidemiological systems resulted from an infectious process, operating in continuous time, combined with the pig breeding process that was modeled based on discrete events occurring instantaneously. We used this model to simulate JEV transmission within a continuum of plausible pig breeding systems encountered in SEA, ranging from backyards to semi-commercial systems. We then analyzed the joint effects of the three tested control measures, namely sow vaccination, pig herd management and vector control, on several indicators characterizing (i) the ability of different pig breeding systems to be simultaneously profitable and allow JEV eradication in the herd, (ii) the impact of JE on pig production and the profitability of gilt vaccination, and (iii) the risk for human beings living in the vicinity of pig herds and/or near pig slaughterhouses. According to our model, herd management has no effect on JEV circulation. Vector control alone is a major control tool but shows paradoxical effects that should be considered in any mosquito based control strategy. Combining sow vaccination and vector control could be an alternative or an additional measure to human vaccination to efficiently reduce both JE incidence in humans and the economic impact of JE infection on pig farms. Author summary Japanese Encephalitis (JE) still has an important impact on human health in Southeast Asia. Human vaccination is an efficient tool to protect humans but it may not be effective against emerging strains, and poor or remote population may not be able to afford it. Severe outbreaks still occur. JE virus (JEV) is primarily transmitted between pigs and mosquitoes. When infected after sexual maturity, pigs show reproduction disorders leading to economic losses. We propose a modelling approach to investigate the joint effect of three additional control measures, namely sow vaccination, vector control, and pig herd management on JEV transmission dynamic, risk for humans and pigs, and pig breeding sustainability. According to our results, vector control, associated or not with sow vaccination, may be an efficient tool to reduce JE incidence in both human and pigs.