Seroprevalence trends of leptospirosis at a tertiary care centre of North India from 2016-2019 determined by two commercial elisa kits

Abstract

Leptospirosis is a worldwide zoonotic disease which remains under diagnosed in most of the regions of our country due to the lack of proper diagnostic facility and set up. Diagnosis usually depends on Microscopy,culture and serological tests like ELISA, MAT(Microscopic agglutination test). MAT is the gold standard diagnostic test but it requires live leptospires and it can only be done in a reference laboratory. Hence, ELISA is the most preferred cost-effective serological method with both sensitivity and specificity of 95%. The Aim of our present study was to evaluate the trends of seroprevalence of leptospirosis from January 2016 to December 2019 and to compare two ELISA kits for the serodiagnosis of Leptospirosis. The study was conducted between January 2016 to December 2019 and 1611 blood samples were collected from clinically suspected cases of leptospirosis. Detection of IgM antibodies to leptospira was done by DRG andRecombilisa (CTK) ELISA kits. Results by both the kits were analysed. Seventy samples were taken as controls from different patients on random basis to prevent any type of biasing. Samples were tested for other co-infections and Demographic parameters were studied. Seroprevalence was estimated to be 4.8% by DRG KIT and 5.5% by Recombilisa CTK kit. Average seroprevalence was noted to be 5.1%. The diagnosis of presumptive and possible Leptospirosis was made in 96(78%) and 27(22%) respectively, by modified Faine’s criteria. The seroprevalence between 2016 to 2019 varied from 0.57 – 1.8 % . The months of July to November of year 2017 noted the highest prevalence. Out of these patients, majority (96%) showed significant improvement during the follow–up period after 2-3 months with empirical treatment. Typhoid was seen as most common co- infection in these patients.