Development of a magnetic bead fluorescence microscopy immunoassay to detect and quantify Leptospira in environmental water samples

► We developed a fluorescence microscopy assay for detecting environmental leptospires. ► Leptospires were well visible using single and multiple serovar assay variants. ► Assay detection limits in real water samples ranged between 101 and 102 cells per mL. ► Applicability of the single serovar assay was shown in a pilot field study.