Fig. 6

Density map of the relationship between socio-economic factors (GDP and population density) and average brucellosis cases between 2004 and 2017 in mainland China. In both figures, one dot = 200 human brucellosis cases. The GDP and population density of the southeastern coastal and central provinces were higher than those of the northwest regions. Most of the brucellosis cases were distributed in the northern, northwestern, and northeastern provinces