Abstract

The objective of this research focused on evaluation of membrane filters application for isolation of Leptospira from surface water samples. The filter materials evaluated included nitrocellulose (0.22 and 0.45 µm pore diameters), polyvinylidene fluoride (Durapore 0.22 and 0.40 μm pore diameters), nylon mesh (37 μm), and glass fiber (1.0 µm). Millipore polyvinylidene fluoride filter (0.22 μm) was examined by scanning electron microscopy to verify that leptospires were present following filtration. Our results suggest for isolate nearly 100% ofLeptospira from water samples, the optimal pore diameter should be less than 0.45 µm (a standard pore size used to detect indicator microorganisms in 100 ml of water). Although filtration method can be used to isolation leptospires from surface water samples, it is unclear whether this is a useful method for detection of all leptospires exist within surface water samples. Accordingly, a large proportion of leptospires can be retained by membrane filter with a pore diameter commonly used to isolate leptospires from surface water samples (0.45 µm pore size).

Key words: Leptospira, filtration technique, leptospirosis.