Development of a rapid and sensitive recombinase polymerase amplification-lateral flow assay for detection of Burkholderia mallei.

Burkholderia mallei, a potential biothreat agent is the aetiological agent of glanders, a zoonotic disease primarily affecting equines. B. mallei shares close genetic proximity with B. pseudomallei, the aetiological agent of melioidosis. Hence, molecular detection of B. mallei and its differentiation from B. pseudomallei has always been challenging. Early diagnosis of glanders is critical for timely treatment in humans and disease containment in animals. In this study a recombinase polymerase amplification-lateral flow (RPA-LF) assay has been developed for early and accurate detection of B. mallei. RPA-LF assay was found to be highly sensitive and detected as low as 10 fg genomic DNA of B. mallei. The assay was highly specific and could differentiate B. mallei and B. pseudomallei. The assay also detected B. mallei in artificially spiked blood, tap water and garden soil. The established assay is simple, rapid and does not require complex instrumentation. The field deployable assay can have better implications in rapid glanders diagnosis and environmental detection of B. mallei over PCR-based detection tools in glanders endemic areas with limited laboratory resources.