Leptospirosis is a potentially serious but treatable zoonotic disease representing a worldwide public health hazard. Its symptoms may mimic those of a number of other unrelated infections such as influenza meningitis hepatitis dengue or viral haemorrhagic fevers. It is important to distinguish leptospirosis from these diseases. For this reason new diagnostic methods have been developed in recent years. In humid tropical and subtropical areas where most developing countries are located leptospirosis poses a greater health problem than in areas with a temperate climate. Because leptospirosis is