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The ongoing circulation of Highly Pathogenic Avian Influenza (HPAI) H5N1 poses a threat to both poultry and public health. Adapting the constructs of the Health Belief Model (HBM) framework, we investigated perceptions of backyard, commercial broiler and layer chicken farmers to implement HPAI prevention and control measures in Bangladesh. Two cross‐sectional studies were conducted in 2016 and 2017 on 144 backyard, 106 broiler and 113 layer chicken farms. Using Structural Equation Modelling, we modelled the direct and indirect effects on farmers' perceptions on taking HPAI prevention and control actions. Our results indicate that farmers of different chicken production systems have different decision‐making processes. While perceived barriers to the implementation of prevention and control measures (e.g. wearing protective equipment when handling chickens) prevented both broiler and backyard farmers to adopt interventions, perceived benefits of measures (e.g. maintaining high biosecurity will reduce the risk of birds becoming sick) strongly influenced commercial farmers' decisions, but not backyard farmers' decisions. Information provided on HPAI through media, meetings or via information campaigns played an important role in farmers' decision‐making in all production systems. Outcomes of this research can be used to tailor advice on HPAI control and prevention to different poultry farming groups by accounting for specific factors influencing their decision‐making, instead of using one‐size‐fit‐all communication approach.

In order to control Highly Pathogenic Avian Influenza (HPAI) H5N1 and Low Pathogenic Avian Influenza (LPAI) H9N2 virus spread in endemically infected countries, a detailed understanding of infection patterns is required. We conducted cross‐sectional studies in Bangladesh in 2016 and 2017, on 144 backyard, 106 broiler and 113 layer chicken farms. Although all sampled birds were negative for H5 virus by RT‐PCR, H5 antibodies were detected in unvaccinated birds on all three farming systems. Higher H5 antibody prevalence was observed in ducks raised on backyard farms, 14.2% (95% CI: 10.0%–19.8%), compared to in‐contact backyard chickens, 4.2% (95% CI: 2.8%–6.1%). The H5 antibody prevalence was lower in broiler chickens, 1.5% (95% CI: 0.9%–2.5%), compared to layer chickens, 7.8% (95% CI: 6.1%–9.8%). H9 viruses were detected by RT‐PCR in 0.5% (95% CI: 0.2%–1.3%) and 0.6% (95% CI: 0.3%–1.5%) of broilers and layers, respectively, and in 0.2% (95% CI: 0.0%–1.2%) of backyard chickens. Backyard chickens and ducks showed similar H9 antibody prevalence, 16.0% (95% CI: 13.2%–19.2%) and 15.7% (95% CI: 11.3%–21.4%), which was higher compared to layers, 5.8% (95% CI: 4.3%–7.6%), and broilers, 1.5% (95% CI: 0.9%–2.5%). Over the course of a production cycle, H5 and H9 antibody prevalence increased with the age of backyard and layer chickens. Usually, multiple ducks within a flock were H5 antibody positive, in contrast to backyard chickens, broilers and layers where only individual birds within flocks developed H5 antibodies. Our findings highlight low virus circulation in healthy chickens of all production systems in Bangladesh, which is in contrast to high virus circulation reported from live bird markets. Data generated in this project can be used to adopt risk‐based surveillance approaches in different chicken production systems in Bangladesh and to inform mathematical models exploring HPAI infection dynamics in poultry from the source of production.

We review the nature of interdisciplinary research in relation to One Health, a perspective on human-animal health which would appear to merit close interdisciplinary cooperation to inform public health policy. We discuss the relationship between biological sciences, epidemiology and the social sciences and note that interdisciplinary work demands attention be given to a range of often neglected epistemological and methodological issues. Epidemiologists may sometimes adopt social science techniques as “bolt-ons”1 to their research without having a complete understanding of how the social sciences work. The paper introduces a range of social science concepts and applies them to the challenges of understanding and practicing participatory and local epidemiology. We consider the problem of co-production of knowledge about One Health and zoonotic diseases in relation to funding structures, working in large international teams and explore some of the often-neglected realities of working across disciplines and cultures. We do this in part by applying the concept of value-chain to the research process.

Today, brucellosis is the most common global bacterial zoonosis, bringing with it a range of significant health and economic consequences, yet it is rarely identified from the archaeological record. Detection and understanding of past zoonoses could be improved by triangulating evidence and proxies generated through different approaches. The complex socio‐ecological systems that support zoonoses involve humans, animals, and pathogens interacting within specific environmental and cultural contexts, and as such there is a diversity of potential datasets that can be targeted. To capture this, in this paper we consider how to approach the study of zoonotic brucellosis in the past from a One Health perspective, one which explicitly acknowledges the health link between people, animals and environments (both physical and cultural). One Health research is explicitly interdisciplinary and conceptually moves away from an anthropocentric approach, allowing the component parts to be considered in holistic and integrated ways to deliver more comprehensive understanding. To this end, in this paper we review the methods, selected evidence and potential for past brucellosis identification and understanding, focussing on osteological markers in humans and animals, historical, biomolecular and epidemiological approaches. We also present an agenda and potential for future research.

We conducted a cross-sectional study in live bird markets (LBMs) in Dhaka and Chittagong, Bangladesh, to estimate the prevalence of avian influenza A(H5) and A(H9) viruses in different types of poultry and environmental areas by using Bayesian hierarchical logistic regression models. We detected these viruses in nearly all LBMs. Prevalence of A(H5) virus was higher in waterfowl than in chickens, whereas prevalence of A(H9) virus was higher in chickens than in waterfowl and, among chicken types, in industrial broilers than in cross-breeds and indigenous breeds. LBMs with >1 wholesaler were more frequently contaminated by A(H5) virus than retail-only LBMs. Prevalence of A(H9) virus in poultry and level of environmental contamination were also higher in LBMs with >1 wholesaler. We found a high level of circulation of both avian influenza viruses in surveyed LBMs. Prevalence was influenced by type of poultry, environmental site, and trading patterns because our study included previously collected data.

Avian influenza is a major animal and public health concern in Bangladesh. A decade after development and implementation of the first national avian influenza and human pandemic influenza preparedness and response plan in Bangladesh, a two-stage qualitative stakeholder analysis was performed in relation to the policy development process and the actual policy. This study specifically aimed to identify the future policy options to prevent and control avian influenza and other poultry-related zoonotic diseases in Bangladesh. It was recommended that the policy should be based on the One Health concept, be evidence-based, sustainable, reviewed and updated as necessary. The future policy environment that is suitable for developing and implementing these policies should take into account the following points: the need to formally engage multiple sectors, the need for clear and acceptable leadership, roles and responsibilities and the need for a common pool of resources and provision for transferring resources. Most of these recommendations are directed towards the Government of Bangladesh. However, other sectors, including research and poultry production stakeholders, also have a major role to play to inform policy making and actively participate in the multi-sectoral approach.

Live bird markets are often the focus of surveillance activities monitoring avian influenza viruses (AIV) circulating in poultry. However, in order to ensure a high sensitivity of virus detection and effectiveness of management actions, poultry management practices features influencing AIV dynamics need to be accounted for in the design of surveillance programmes. In order to address this knowledge gap, a cross-sectional survey was conducted through interviews with 791 traders in 18 Vietnamese live bird markets. Markets greatly differed according to the sources from which poultry was obtained, and their connections to other markets through the movements of their traders. These features, which could be informed based on indicators that are easy to measure, suggest that markets could be used as sentinels for monitoring virus strains circulating in specific segments of the poultry production sector. AIV spread within markets was modelled. Due to the high turn-over of poultry, viral amplification was likely to be minimal in most of the largest markets. However, due to the large number of birds being introduced each day, and challenges related to cleaning and disinfection, environmental accumulation of viruses at markets may take place, posing a threat to the poultry production sector and to public health.

Tracing movements could assist the implementation of bio-containment measures during a disease outbreak. To evaluate the potential for implementing a tracing system for a poultry supply chain in northern Vietnam, a four-month longitudinal study was conducted to identify marketing practices associated with poultry traceability. Poultry sold in batches were traced between farms and markets, and their traceability was assessed upon market arrival. A total of 315 batches were released from the farms; 37% arrived at a market, from which 57.3% were 'traceable'. The results of the multivariable analysis showed that traceability was associated with farms operating through no more than two traders (Odds ratio [OR] = 5.97, 95% CI 1.15-30.92) and batches brought to the market on the day of purchase (OR = 4.05, 95% CI 1.23-13.27). No specific incentives were provided to farmers or traders. Results suggest that there is potential for implementing a poultry traceability scheme, although the tracing methodology should be refined.

International audience

The genetic control of the immune response to DNA was studied in various strains of mice F1 hybrids and corresponding back-crosses immunized with single stranded DNA complexed to methylated bovine serum albumin. Anti-DNA antibody response was measured by radioimmuno-logical technique. High responder, low responder, and intermediate responder strains were found and the ability to respond to DNA was characterized as a dominant genetic trait which is not linked to the major locus of histocompatibility. Studies in back-crosses suggested that this immune response is under multigenic control. High responder mice produce both anti-double stranded DNA and anti-single stranded DNA 7S and 19S antibodies, while low responder mice produce mainly anti-single stranded DNA 19S antibodies.

International audience