Decreasing trend of seroprevalence of leptospirosis at All India Institute of Medical Sciences New Delhi: 2014–2018

BACKGROUND: Leptospirosis is an important emerging public health problem in India. There is limited information regarding the seroprevalence of leptospirosis in population from northern states of India. This study reports result of a 4-year-retrospective sero-epidemiological survey of leptospirosis conducted in a teaching tertiary care hospital in New Delhi, India. The aim of our study was to explore seroprevalence and clinical pattern of disease occurrence in suspected cases of leptospirosis and to search for any co-existing infections in northern areas such as New Delhi, India. METHODS: The patients with clinically suspected leptospirosis who attended outpatient or admitted to the Departments of Medicine, Gastroenterology, Pediatrics and Neurology, etc. of our hospital were retrospectively analyzed. The qualitative determination of anti-leptospira-specific immunoglobulin (IgM) antibodies was carried out using commercially available enzyme-linked immunosorbent assay (ELISA) kit (Panbio Diagnostics, Brisbane, Australia). RESULTS: Of these 1545 patients, 6.47% (100/1545) were seropositive for anti-leptospira-specific immunoglobulin (IgM) antibodies. Using modified Faine's criteria, a diagnosis of presumptive and possible leptospirosis was made in 79/100 (79%) and 21/100 (21%) patients. Significant declining trend of seroprevalence rate of leptospirosis from 26.90% in 2000–2010 and 20% in 2011–2014 to 6.47% in 2014–2018 (P value <0.05) in our referral tertiary care center. Seventeen patients showed co-infection with other common pathogen prevailing locally. CONCLUSION: There is a need to increase awareness among public and clinicians, however, more region/province-wise studies on seroprevalence of leptospirosis are required to improve our understanding of the actual burden.