Detecting Leptospira in water: evaluation of a proposed method

Abstract

Leptospirosis is the most widespread zoonosis in the world, and its geographic distribution is spreading. The disease is caused by Leptospira, a pathogenic group of spirochetes transferred between a variety of maintenance and accidental hosts. Few management practices exist because little is known about leptospire ecology and there is no reliable method for environmental detection. The goal of this work is to evaluate a two part methodology that isolates and detects pathogenic Leptospira in water. The first study uses suspensions of Leptospira, visually quantified in cells per milliliter, to evaluate the transmittance of different filters. The second study evaluates the sensitivity of a PCR detection method under real-world conditions. Results indicate a 0.2µm nitrocellulose filter is the optimal choice for filtration, and microbial DNA can be consistently recovered from used filter surfaces. Additional research will be necessary before this method can be used for field testing.