Controlling and monitoring emerging zoonoses in the poultry farming and trading system in Bangladesh: an interplay between pathogens, people, policy

Early in the 20th century, about 20 million people died from a great influenza epidemic which swept across the whole world. Since then, there have been other, smaller but still significant global influenza epidemics. Influenza is a zoonotic disease. It is caused by a family of viruses which live in pigs, poultry, humans and some other animals and birds, both domestic and wild. It is able to shift genetic material around between different versions of the virus found in these diverse species. This ability to for influenza viruses to combine and change makes it hard to develop generally effective vaccines for different strains. Global and national health authorities are constantly on the lookout for signs that a new global pandemic of this potentially fatal disease is about to move from a localised outbreak to a global pandemic.
Increases in living standards and in global trade mean that there is a rapidly rising demand for and supply of animal protein. Poultry and specifically chickens are the major source of all protein consumed in the world. Bangladesh is undergoing large changes in economic and social development. Poverty alleviation through livestock production plays an increasing part in these developments. Due to their high reproduction and growth rates as well as the ease of scaling up production from backyard to large industrial farms, poultry production adapts better than any other livestock sector to increased demand, and will further expand in the near future. But with these advantages comes increased risk of outbreaks of novel influenza strains, some of them highly pathogenic, as in the case of the recent H5N1. Such outbreaks can have up to 100% mortality in chickens and other domestic poultry and very high mortality rates in human beings when the influenza "jumps" species from the animal/bird reservoir to humans - a process called zoonosis.
In the face of disease outbreaks in poultry, farmers and traders worry about economic loss. They may change their behaviour to avoid such loss and in the process may facilitate the spread of infection. Such behavioural changes can modify the way disease spreads, and even prolong and strengthen the epidemic so that it becomes a widespread "pandemic" moving beyond a local area to the whole world. This research will study the behaviour of people working in the Bangladeshi poultry farming and trading system so as to understand how to develop effective policies which will (a) reduce the risk that people's behaviour will spread the disease (b) develop practical and effective interventions which will control widespread disease dissemination.
The team will do this by combining two areas of work: (a) sophisticated mathematical modelling of how poultry production and marketing works; (b) detailed qualitative and quantitative study of the social, cultural and economic factors which may promote disease maintenance and dissemination in Bangladesh. An innovation in this study will be the inclusion of an experimental component whereby farmers and traders will be asked to play a number of epidemiological "games". This approach will mean that the insights from the qualitative study of cultural socio-economics will feed into a more sophisticated understanding of people's behaviour in the face of disease outbreaks. This in turn will enable refinement of the systems modelling component of the project.
The approaches we will adopt in this research will produce both specific local knowledge and more general knowledge which will be useful for understanding influenza outbreaks and even some aspects of other animal and human infectious disease outbreaks and pandemics in other parts of the world.

The trade of live birds, a common practice in Bangladesh, provides smallholders with an important source of income and can provide a route out of poverty. However, it can also play a major role in the transmission of zoonotic pathogens, such as avian influenza viruses (AIV). The structure of the network shaped by the movements of live bird traders influences the potential of a pathogen to invade the poultry population, the scale of the epidemic, and the level of human exposure. Outbreaks of zoonotic diseases negatively impact on the health and livelihoods of poultry production stakeholders. In the face of an outbreak, key stakeholders may change their farming and trading practices in order to reduce this impact, thus triggering changes in the structure of the trade networks. These changes will, in turn, affect the potential of a pathogen to spread, as well as the efficacy of any mitigation strategies attempting to control the disease.
In this project, we aim to identify the socio-economic, cultural, and epidemiological factors that shape the structure of live bird trade networks in Bangladesh, and the types of changes in the network structure which could facilitate the emergence of zoonotic pathogens and influence their maintenance and dissemination. Based on this understanding of the underlying system behaviour, the project seeks to develop novel control and surveillance strategies tailored to the evolving characteristics of live bird trade networks.
Employing an inter-disciplinary perspective, this project will involve a combination of traditional ethnographic techniques, such as observations and semi-structured interviews, innovative techniques using methods developed in experimental economics, biological sampling from both humans and poultry, and the development of joint epidemiological and socioeconomic models. AIV, in particular H5N1, will be used as a model to study the traders' and farmers' responses to disease risk.

Highly pathogenic avian influenza H5N1 (HPAI H5N1) is endemic in poultry in Bangladesh and particularly affects small-holder farmers. This detailed study of risk perceptions and behavioural adaptations among people who work intimately with poultry will generate practical, evidence-based policy recommendations that promote livelihoods and are also relevant to public health, animal health, agriculture, and trade sector policy-makers in Bangladesh.
Public health risk posed by HPAI H5N1 and other emerging zoonotic diseases are primarily addressed after they are diagnosed in the human population. This project aims to alter strategy and priorities in the policy environment, from emergency response to prevention at the source. The emphasis will be directed away from particular pathogens towards the characteristics of the human-animal systems that maintain and spread these diseases. This will foster a significant shift in how policy makers address disease control and surveillance programming.
Recognition of the inter-related social, economic, cultural, and biological drivers underlying disease spread and maintenance will minimise unintended impacts which are often associated with top-down policies like market closure and culling; unintended impacts include under-reporting, loss of livelihood, illegal trade, and poultry smuggling. Policy recommendations will not only improve disease control and surveillance, but also create conditions for achieving a sustainable reduction in smallholders' vulnerability, both in terms of health and livelihoods. Women are primarily responsible for rearing poultry in much of Bangladesh and thus policy recommendations will aim to benefit these key stakeholders. Given that this research focuses on the characteristics of the human-animal system, recommendations will be tailored to these systems, in turn contributing to the resilience of the production system to zoonotic disease emergence and, ultimately, promote livestock keeping as a durable pathway out of poverty. Importantly, policy recommendations will also be relevant for the surveillance and control of present and future disease emergences in Bangladesh.
The translation of research outputs into policy recommendations, and subsequently into action, will be promoted through continuous engagement throughout the course of this project with policy-makers, NGOs, and poultry production stakeholders in Bangladesh. The feasibility, acceptance of, and likely compliance to, potential control strategies and surveillance schemes will be assessed, and workshops will be held to inform stakeholders of research findings, and to introduce them to different measures - such as behavioural changes - that may allow them to reduce the risk for their own health and livelihood. The uptake of research in policy will be fostered by policy consultations to identify policy gaps and institutional barriers across sectors to the implementation of potential interventions. This will ensure that research outputs are presented in the most appropriate form and communicated through the most appropriate routes, as well as promoting a durable interaction between the policy environment and the research community in Bangladesh.
Although these recommendations will be tailored to the characteristics of the poultry sector in Bangladesh, the inter-disciplinary approach developed for this project will be generalizable, and key findings will be extrapolated to be adaptable for other contexts, and to foster sustainable relationships across sectors for the surveillance and control of zoonotic disease threats. To ensure a wide audience for findings, Chatham House roundtables, organised at the beginning and at the end of this project, will involve international beneficiaries, including: international organizations such as WHO, FAO and OIE, and policy-makers involved in livestock trade, and the veterinary and public health sectors from other Asian countries where HPAI H5N1 is recurrent or endemic.