Leptospirosis in man and rodents in North and Northeast Thailand

A seroepidemiological study of leptospirosis in man and rodents in the North and Northeast Thailand revealed that 0.27% of the rural people from three different ecologic areas were positive. The positivity rate has dropped dramatically when compared to a previous survey (28%). Of 1,135 wild rodents studied, 42 of 365 (11.5%) B. indica and 50 of 676 (7.4%) R. rattus were serologically positive. Others were negative. Only two of 157 R. rattus had positive cultures in which L. javanica and L. autumnalis were isolated. The study shows that wild rats are naturally implicated in human disease as a common reservoir and that the yearly rat eradication campaigns attributed as one of the effective factors in a major reduction of disease to a level of non significant public health hazard.