Diagnosis of leptospirosis in animals: challenges and perspectives

Leptospirosis is a life-threatening zoonotic disease with a major public and animal health impact. Annually, approximately 1.03 million people are affected by leptospirosis, but our understanding of its impact on animals is limited. The epidemiology, pathogenesis, clinical presentation, diagnostic methods, and control measures for this disease differ significantly between humans and animals. This difference is due in part to the wide range of animal species that can be infected, the different infecting serovars present across species and geographic regions, and the existence of chronic asymptomatic reservoirs. Additionally, diagnosing leptospirosis in animals is complicated by the limited availability of sensitive, specific, and affordable diagnostic tools that can be employed at the point of care. There is often a trade-off between the sensitivity/specificity and accessibility of these diagnostics, and no single diagnostic test is entirely reliable. Many newer diagnostic methods lack validation for use in various animal species and clinical samples. In this minireview, we discuss the methods used for detecting Leptospira-infected animals and challenges associated with these techniques.