Rapid and visual loop mediated isothermal amplification (LAMP) test for the detection of Brucella spp. and its applicability in epidemiology of bovine brucellosis

Brucellosis is a devastating disease, once an abortion stoma starts in a herd, and hence early diagnosis is important. Loop mediated isothermal amplification (LAMP) has enlightened the darker part of the diagnostic world by its simplicity and swiftness, and has the advantage of working in isothemial conditions so that it can be applied to the field. LAMP for Brucella spp., that already exists has not been exploited for visual detection and the time needed for completion of the reaction has not been reduced. In the present study, an attempt was made to seal these cracks by developing a fast and visually detectable LAMP for Brucella spp., which needs only 30 min detection time, and SYBR green aided easier result visualization. The LAMP test targeting the omp25 gene was found to be highly sensitive and specific for detecting Brucella spp. Comparison of the LAMP test with the available PCR assay revealed that the LAMP test was more sensitive than PCR, following testing of 438 field samples of cattle origin, and it showed prevalence of Brucella of 14.7 % in different parts of India. Being highly sensitive, specific and speedy, the standardized visual LAMP test can be widely used for epidemiological surveys of this economically important and zoonotic pathogen.