Sam Abraham

Members of the genus Leptospira are classified into more than 20 species based on DNA relatedness and comprise over 350 serovars, based on surface agglutinating lipopolysaccharide antigens. However, they are best viewed as three groupings. Saprophytic species, e.g., Leptospira biflexa, are never associated with disease. Members of the pathogen group, e.g., Leptospira interrogans and Leptospira borgpetersenii, cause leptospirosis in humans and animals worldwide, with infection resulting in a range of syndromes from mild or asymptomatic infection to severe forms involving multiple organ failure and death. An intermediate group containing, e.g., Leptospira fainei and Leptospira licerasiae, may be associated with infection and mild disease (1, 2).