FIG. 1.

Map of case distribution and divisions for the melioidosis serosurveillance. The melioidosis cases in Taiwan (2001 to 2006) are indicated on the right-hand side. The numbering indicates the numbers of cases in specific areas. The incidence of melioidosis in clusters of cases in 2005 is listed to the upper right of the indicated number of cases. The surrounding areas of the Er-Ren River Basin are enlarged in the map on the left. The letters A, B, and C indicate the regions with distinct seropositive rates for melioidosis or different isolation rates for B. pseudomallei (see text). Region A was subdivided into sites A1 and A2 because the two sites are separated by the river and the agriculture involves dramatically different crops.