Quantifying the transmission routes of gastroenteritis in Pakistan and developing targeted interventions Gastroenteritis is an infection of the stomach and the intestine by harmful bacteria, and other similar microbes, such as viruses. It causes diarrhoea and dehydration, which can be easily complicated in areas of the world where clean water is in short supply. The disease is a major health problem in Pakistan, where it is estimated to be responsible for nearly 60,000 deaths annually. Indeed, in Pakistan, 38% of children under five years old have received treatment for diarrhoea at some point in their lives.   In this project, our project team of social scientists, microbiologists, engineers, epidemiologists, chemists and statisticians will combine to take a genuinely inter-disciplinary approach to understanding the various social, biological, chemical and technical factors affecting the spread of gastroenteritis through agriculture, sanitation, drinking water, food, and person-to-person contact. A significant effort will be made to understand the social attitudes to water, sanitation, hygiene and how those link to agriculture, food and the way communities live their lives. At the same time, the information obtained from studying those cultural issues will be used to help decide on a plan for sampling water and other environmental samples for chemical and biological measurements and experiments.   We will focus on some important bacteria and parasites associated with gastroenteritis. Tests will be developed that allow us to rapidly detect those target bacteria (Campylobacter and E.coli) and parasites (Cryptosporidium and Giardia) based on DNA sequencing technology. Among these, Campylobacter is particularly strongly associated with growth-stunting in children. We have recently developed new tests in the UK to allow for rapid detection of the bacteria associated with tuberculosis (bTB) in cows, and we will adapt that technology in Pakistan for gastroenteritis.  The development of such low-cost, easily portable, and reliable tests for rapid detection of harmful bacteria and parasites will be a groundbreaking development for disease surveillance and prevention.  As part of the project, we will also test the various transmission routes of those bacteria in causing gastroenteritis. To do this, we will set up experiments to, for example, explore the transmission of harmful bacteria from soil or water into leaf crops, root vegetables and fruit.   We will also involve a wide variety of social partners. We will use surveys and run facilitated workshops to meet the various people with a stake in clean water and food, good sanitation, and public health. This includes households, tenants and landlords; community leaders; politicians; local and central government; governmental agencies, including those responsible for environmental protection; academic partners in the local universities; water and wastewater companies; the farming community; medical personnel; public health experts and administrators; and a wide variety of NGOs and development agency representatives, including UNICEF.   The project will generate a large amount of information about the cultural issues affecting the transmission of harmful bacteria such as Campylobacter, as well as technical information on the means of infection. Importantly, useful tests will be developed to help significantly improve the ability of experts in Pakistan to monitor harmful bacteria and prevent infections. We also see important opportunities for transferring our knowledge and technology further afield to other low- and middle-income countries. The Global Challenges Research Fund (GCRF) supports cutting-edge research to address challenges faced by developing countries. The fund addresses the UN sustainable development goals. It aims to maximise the impact of research and innovation to improve lives and opportunity in the developing world.