The investigators will collect two data sets each in Lao PDR and Thailand: the first contains district-level representative health behaviour of approx. 2,400 adults across 30 rural communities per country (4,800 in total; representing rural populations of approx. 1-2 million adults); the second is a complete social network census of approx. 1600 adults each in three rural communities per country (approx. 4,800 in total). Within the sampled villages, the investigators will complete checklists about existing formal and informal healthcare facilities and gather patient load data from primary care units catering to the respective villages. As part of the questionnaire testing process, the investigators will conduct (and collect as primary data) cognitive interviews to improve the survey tool, to interpret our data, and to justify our methodological choices. The investigators will carry out the district-level village survey in one round, and the village-level social network censuses in two rounds. Between the two village social network censuses, the investigators will engage in public engagement activities in the selected villages (focused on antibiotic use) and re-survey all adults in the three villages per country two to three months later.