BEYOND CONVENTIONAL TECHNOLOGIES: NEXT-WAVE DIAGNOSTICS FOR LEPTOSPIROSIS IN INDIA

Abstract

Leptospirosis is an important, underrecognized disease posing significant consequences for livestock production as well as public health. Among the different livestock species, buffaloes represent a major reservoir host, which in turn directly impacts the dairy as well as beef sectors of India, as buffaloes are the higher contributors in both sectors among all livestock of this country. This disease is caused by pathogenic Leptospira spp., and direct or indirect contact with contaminated urine, water, soil, or infected animals is the main source of its transmission. Infection of this disease is commonly associated with infertility, abortion, stillbirth, and reproductive losses in the animals, and in the case of humans, it may range from nonspecific febrile illness to multiorgan failure, like liver, kidney, lung, and central nervous system failures. In India, due to several reasons, like limited diagnostic infrastructure, nonspecific clinical presentation, and lack of awareness among at-risk populations and health professionals, this disease remains significantly underdiagnosed and underreported, despite its wide distribution in this country. This review presents and summarizes the important diagnostic techniques currently available for leptospirosis and classifies them as conventional, advanced, and cutting-edge. Conventional methods are widely used, such as microscopy, culture, serology, and rapid assays, but due to lower sensitivity, they are not very reliable for early detection of disease. Molecular strategies like conventional PCR and its variants, viz., nested PCR, qPCR, LAMP, and Truenat™, provide improved sensitivity and also offer earlier detection. Most recent and newly developed diagnostic methods, including biosensors, CRISPR-based assays, and next-generation sequencing, further enhance the speed and deliver higher precision in diagnosis. Expanding disease surveillance; strengthening already available diagnostic capacity and infrastructure and integrating with advanced technologies; and improving public awareness are crucial components for reducing disease burden, supporting timely treatment, and protecting both animal productivity and human health in India.