Analysis of Prevalent Leptospira Serovar in Different Animals of South Gujarat Region during the Year of 2020

Aim of Study: Leptospirosis is a bacterial zoonotic disease transmitted through contact with animals that are harbouring leptospira. Knowledge of prevalent leptospira in a particular animal of a particular geographical area is essential to understand the epizootiology of disease, to understand the linkage between circulating serovars in animals and in humans, and to apply appropriate control measures, etc. Material and Methods: Animal samples from different districts of the south Gujarat region received in the Microbiology department during the year of 2020 for the Microscopic agglutination test (MAT) of leptospirosis were included in the study. Results of MAT which was already performed using 12 different serovars were analysed to prevent serovars in a particular animal. Quantitative data were analysed using frequency and percentage. Result: Out of 1406 animal samples, 151 (11 percent) were positive from animals like cows, buffalos, bullocks and goats. More prevalent serovars in cows were L. ictrohemorrahiae (22%), L. hardjo (19%), L. patoc (17%) and L. pyrogen (16%). In buffalo, L. patoc (58%) and L. hardjo (27%) were found. L. hardjo (50%) in bullock and L. automonalis (50%), L. australis (22%) and L. patoc (14%) in goat were found as prevent serovars. Conclusion: Different prevent serovars has been observed in different animals from the different district south Gujarat region which will be helpful to trace the source of infection in human, to apply control measures, to know the epizootiology of disease, for developing strategies in the future during vaccine development with emphasizing more on the prevalent serovars.

A novel luciferase immunosorbent assay performs better than a commercial enzyme-linked immunosorbent assay to detect MERS-CoV specific IgG in humans and animals

The Middle East respiratory syndrome(MERS)is a lethal zoonosis caused by MERS coronavirus(MERS-CoV)and poses a significant threat to public health worldwide.Therefore,a rapid,sensitive,and specific serologic test for detecting anti-MERS-CoV antibodies in both humans and animals is urgently needed for the successful management of this illness.Here,we evaluated various novel luciferase immunosorbent assays(LISA)based on nucleocapsid protein(NP)as well as fragments derived from spike protein(S)including subunit 1(S1),N terminal domain(NTD),receptorbinding domain(RBD)and subunit 2(S2)of S for the detection of MERS-CoV-specific IgG.Fusion proteins,including nanoluciferase(NLuc)and various fragments derived from the NP or S protein of MERS-CoV,were expressed in human embryonic kidney 293 T cells.LISAs that detected anti-MERS-CoV IgG were further developed using cell lysates expressing various fusion proteins.Panels of human or animal samples infected with MERS-CoV were used to analyze the sensitivity and specificity of various LISAs in reference to a MERS-CoV RT-PCR,commercial S1-based ELISA,and pseudovirus particle neutralization test(ppNT).Our results showed that the S1-,RBD-,and NP-LISAs were more sensitive than the NTD-and S2-LISAs for the detection of anti-MERS-CoV IgG.Furthermore,the S1-,RBD-,and NP-LISAs were more sensitive(by at least 16-fold)than the commercially available S1-ELISA.Moreover,the S1-,RBD-,and NPLISA specifically recognized anti-MERS-CoV IgG and did not cross-react with samples derived from other human CoV(OC43,229E,HKU1,NL63)-infected patients.More importantly,these LISAs proved their applicability and reliability for detecting anti-MERS-CoV IgG in samples from camels,monkeys,and mice,among which the RBD-LISA exhibited excellent performance.The results of this study suggest that the novel MERS-CoV RBD-and S1-LISAs are highly effective platforms for the rapid and sensitive detection of anti-MERS-CoV IgG in human and animal samples.These assays have the potential to be used as serologic tests for the management and control of MERS-CoV infection.