A multi-host mechanistic model of African swine fever emergence and control in Romania

<p>Mechanistic epidemiological model of African swine fever emergence in domestic pigs and wild boar for the Romanian epidemic.</p&gt

What can phylodynamics bring to animal health research?

International audienceInfectious diseases are a major burden to global economies, and public and animal health. To date, quantifying the spread of infectious diseases to inform policy making has traditionally relied on epidemiological data collected during epidemics. However, interest has grown in recent phylodynamic techniques to infer pathogen transmission dynamics from genetic data. Here, we provide examples of where this new discipline has enhanced disease management in public health and illustrate how it could be further applied in animal health. In particular, we describe how phylodynamics can address fundamental epidemiological questions, such as inferring key transmission parameters in animal populations and quantifying spillover events at the wildlife-livestock interface, and generate important insights for the design of more effective control strategies.Highlights: Phylodynamics, an increasingly popular statistical framework to infer pathogen transmission dynamics from genetic data, remains overlooked in animal health research. This restricts our ability to design more effective disease control strategies. Phylodynamics can be valuable when investigating the determinants of disease spread, allowing the better targeting of animal populations for disease control and reducing the impact of epidemics. The wildlife–livestock–human interface is critical for disease emergence; thus, promoting phylodynamics at this interface should improve our ability to manage complex epidemics. There is a critical need to improve capacity-building efforts for infectious disease detection in hard-to-sample populations, such as wildlife. Collaborative efforts are needed to make genetic data publicly available in a timely manner during animal disease outbreaks

Role of Live-Duck Movement Networks in Transmission of Avian Influenza, France, 2016–2017

International audienceThe relative roles that movement and proximity networks play in the spread of highly pathogenic avian influenza (HPAI) viruses are often unknown during an epidemic, preventing effective control. We used network analysis to explore the devastating epidemic of HPAI A(H5N8) among poultry, in particular ducks, in France during 2016-2017 and to estimate the likely contribution of live-duck movements. Approximately 0.2% of live-duck movements could have been responsible for between-farm transmission events, mostly early during the epidemic. Results also suggest a transmission risk of 35.5% when an infected holding moves flocks to another holding within 14 days before detection. Finally, we found that densely connected groups of holdings with sparse connections between groups overlapped farmer organizations, which represents important knowledge for surveillance design. This study highlights the importance of movement bans in zones affected by HPAI and of understanding transmission routes to develop appropriate HPAI control strategies

Quantitative Outcomes of a One Health approach to Study Global Health Challenges

Having gained momentum in the last decade, the One Health initiative promotes a holistic approach to address complex global health issues. Before recommending its adoption to stakeholders, however, it is paramount to first compile quantitative evidence of the benefit of such an approach. The aim of this scoping review was to identify and summarize primary research that describes monetary and non-monetary outcomes following adoption of a One Health approach. An extensive literature search yielded a total of 42,167 references, of which 85 were included in the final analysis. The top two biotic health issues addressed in these studies were rabies and malaria; the top abiotic health issue was air pollution. Most studies described collaborations between human and animal (n = 42), or human and environmental disciplines (n = 41); commonly reported interventions included vector control and animal vaccination. Monetary outcomes were commonly expressed as cost-benefit or cost-utility ratios; non-monetary outcomes were described using disease frequency or disease burden measurements. The majority of the studies reported positive or partially positive outcomes. This paper illustrates the variety of health challenges that can be addressed using a One Health approach, and provides tangible quantitative measures that can be used to evaluate future implementations of the One Health approach.Peer reviewe

Phylodynamic analysis of the highly pathogenic avian influenza H5N8 epidemic in France, 2016-2017

In 2016-2017, France experienced a devastating epidemic of highly pathogenic avian influenza (HPAI) H5N8, with more than 400 outbreaks reported in poultry farms. We analyzed the spatiotemporal dynamics of the epidemic using a structured-coalescent-based phylodynamic approach that combined viral genomic data (n = 196; one viral genome per farm) and epidemiological data. In the process, we estimated viral migration rates between departements (French administrative regions) and the temporal dynamics of the effective viral population size (Ne) in each departement. Viral migration rates quantify viral spread between departements and Ne is a population genetic measure of the epidemic size and, in turn, is indicative of the within-departement transmission intensity. We extended the phylodynamic analysis with a generalized linear model to assess the impact of multiple factors-including large-scale preventive culling and live-duck movement bans-on viral migration rates and Ne. We showed that the large-scale culling of ducks that was initiated on 4 January 2017 significantly reduced the viral spread between departements. No relationship was found between the viral spread and duck movements between departements. The within-departement transmission intensity was found to be weakly associated with the intensity of duck movements within departements. Together, these results indicated that the virus spread in short distances, either between adjacent departements or within departements. Results also suggested that the restrictions on duck transport within departements might not have stopped the viral spread completely. Overall, we demonstrated the usefulness of phylodynamics in characterizing the dynamics of a HPAI epidemic and assessing control measures. This method can be adapted to investigate other epidemics of fast-evolving livestock pathogens.ISSN:1865-1674ISSN:1865-168