Fig. 2

Results of Knox test in a matrix. Rows correspond to space distances by steps of 5 m and columns correspond to time distances by steps of 4 days. Values in each cell are estimated excess risk, colored from the lowest (blue) to the highest (red) a; Map of clusters of dengue cases within a space distance of 230 m and time distance of 12 days b; orange circles and numbers represent identified clusters, circle radii only represent cluster extent but not cluster intensity in terms of cases; dots represent location of dengue patients’ household with a fuzzy distance of 20 m around the true position; red dots represent index case, yellow dots represent dengue cases having space-time clustering; green squares represent cases having no space-time clustering; cyan lines represent a possible space-time clustering among cases in each cluster