Human Decoy Trap; operational and social acceptability of novel tool to improve surveillance and control of mosquitoes and other disease vectors Malaria infects over 200 million people every, mostly in sub-Saharan Africa. Nearly half a million people died from the disease in 2015, the majority of deaths being in children under the age of five. The malaria parasite is spread by infected mosquitoes and the most effective way to monitor the disease is to monitor populations of these mosquitoes. However, current tools for sampling malarial mosquitoes are time-consuming and labour intensive, making them expensive and difficult to standardize. Accordingly, data between countries and regions cannot be reliably compared. To solve this problem, we have developed a mosquito trap that exploits the blood-seeking behaviour of mosquitoes by mimicking the sensory stimuli that a mosquito follows when searching for a person to bite. These include the look, smell and temperature of warm-blooded hosts. We have incorporated these stimuli into a trap that lures mosquitoes towards it and then captures them when they land. Our project will test this "Human Decoy" Trap against current methods used in mosquito monitoring to determine whether the Human Decoy Trap can overcome the limitations of existing tools. We will evaluate if Human Decoy Trap catches are suitably similar to those of current traps in terms of numbers of mosquitoes and other important data related to malaria that can be extracted from mosquitoes caught by traps, such as the proportion of caught mosquitoes infected with malaria parasites. Over 90 countries, mostly low and middle income, are malaria-endemic. We will work in Burkina Faso, Benin and Cameroon, three West African countries where malaria causes thousands of deaths every year, but differing in intensity and seasonality of transmission and with different mosquito species involved. This will help us to understand whether there are differences in trap performance in a wide range of malaria settings. In addition, we will work with end-users of the trap, namely local communities, public health operatives and field technicians, to better understand their perspectives and needs regarding mosquito sampling and control. During the course of the project, we will use data we collect to optimize and improve the trap's performance and design. This will help us to develop a commercial prototype that is effective and acceptable to end-users, maximising the likelihood the trap will be adopted into the communities and sectors that need it the most. Longer-term, we envision a version of the Human Decoy Trap that can be deployed as a mosquito control tool. The most effective way of controlling malaria is to reduce the number of infective mosquito bites a person receives. This is currently achieved by providing people with insecticide-treated bed nets to protect them from bites whilst they sleep and spraying the walls inside houses thus killing mosquitoes that rest there. However, neither of these options protects people from mosquitoes that may bite them outdoors during the day or just before they go to bed at night. Data from this current project will be used to provide preliminary evidence for the suitability of the Human Decoy Trap as a control tool that is specifically targeted at malaria mosquitoes biting outdoors, which may also be effective against other species of mosquitoes that can carry other infectious diseases, such as dengue fever, chikungunya and Zika viruses. Such an improved sampling method would enhance the quality of data necessary for efficient targeting and evaluation of malaria control intervention activities and reduce the cost of collecting it. A successful outdoor mosquito control device would help to reduce the population of infected mosquitoes that cause malaria. Ultimately, the combined effect of these tools would be a reduction in the human suffering and death caused by malaria to millions of people every year and an improvement in the social and economic prospects of the 3.2 billion people living at risk of malaria. 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.