Excluding the cluster of cases that occurred during a triathlon in March 2013, the number of cases in the first quarter of 2014 was similar to that of 2013. However, for the first time, a clear increase in cases following a cyclone was observed, and water-based recreational activities were the leading cause of leptospirosis in the first quarter of 2014. After a weather-related incident (hurricane, flooding, etc.), it is important for the public to protect themselves during cleanup or restoration work by wearing gloves, boots, and long sleeves. If clinical symptoms appear after such work or after water-based activities, consult your doctor and inform them of the high-risk activity.