Leptospirosis or Weil’s disease is caused by pathogenic spirochetes belonging to the genus Leptospira which can be found in certain animals and can spread to humans. The bacteria can pass from animals to humans when an unhealed break in the skin is exposed to water or soil that has been contaminated with animal urine. It is not usually transmitted between people. While Leptospira can be grown in culture, this is a fastidious organism and requires immediate transport to the laboratory. Additionally, detectable growth requires prolonged incubation (1-6 weeks), limiting the utility of culture for acute diagnosis. For this reason, serologic detection for antibodies to Leptospira remains the method of choice for rapid diagnosis.