Urbanization is associated with human brucellosis emergence and shifting peri-urban transmission frontiers in China

Urbanization is reshaping socio-ecological interfaces for disease emergence, yet its role in neglected zoonoses remains poorly understood. We investigate how urbanization reconfigures human brucellosis in non-traditional epidemic regions of China. By integrating 18 years brucellosis data from China with statistical modelling and geospatial analysis, we dissect two dimensions of urbanization: the level of urbanization and the physical process of urban expansion. We demonstrate that urbanization level is a primary driver of disease emergence, mediated by expanded transport networks and the marketing of cattle and sheep. Urbanization concurrently shifts the demographic burden towards older and non-local populations. By analyzing the dynamic process of urban expansion, we identified the advancing peri-urban fringe as a shifting transmission frontier where, the highest incidence tracks the outward growth of city boundaries each year. Our findings reveal that urbanization amplifies zoonotic risk by creating and shifting socio-ecological interfaces where transmission concentrates, calling for surveillance and intervention that explicitly targets the dynamic urban-rural gradient. Urbanization reshapes human brucellosis emergence in non-traditional regions of China, increasing risk via transport and livestock trade and shifting transmission to expanding peri-urban fringes according to 18 years of data, statistical modeling, and geospatial analysis.