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Lumpy skin disease (LSD), caused by lumpy skin disease virus (LSDV) of the genus Capripoxvirus, is a notifiable transboundary disease of domestic cattle and has recently spread from eastern Europe [...]

Lumpy skin disease (LSD), an economically important viral disease of cattle caused by lumpy skin disease virus (LSDV) has recently spread into South and East Asia. LSD emerged in India in August 2019, first in Odisha State and spread to other areas, but there is scanty data on source and molecular epidemiology of LSDV involved in the initial outbreaks. Here we report genetic relationships and molecular features of LSDV, causing outbreaks in cattle spanning seven districts in Odisha and West Bengal States during August–December, 2019. Twelve LSDV isolates obtained using lamb testis cells were sequenced and analysed in four complete genes, GPCR, RPO30, P32 and EEV. The phylogenetic analysis revealed that all the Indian LSDV isolates from 2019 outbreaks are very closely related (99.7%–100%) to the historical Kenyan NI‐2490/Kenya/KSGP‐like field strains. Importantly, our results demonstrated that LSDV strains involved in 2019 outbreaks in India and Bangladesh are very similar in GPCR (99.7%), RPO30 (100%) and partial EEV (100%) sequences, indicating a common exotic source of LSDV introduction. Additionally, a 12‐nucleotide insertion was found in GPCR gene of LSDV strains from 2019 outbreaks in India and Bangladesh. The findings of this study highlight the importance of continuous monitoring and molecular characterization of LSDV strains. These data should be useful while developing diagnostic and control strategies against LSD in India. [ABSTRACT FROM AUTHOR]

Natural infections with HoBi‐like pestivirus (HoBiPeV) have been detected in cattle in South America, Europe and Asia with a range of clinical manifestations including fatal mucosal disease (MD). In India, although HoBiPeV in cattle has been reported, there is no information on currently circulating HoBiPeV strains and associated severe clinical disease. Between September 2018 and December 2019, suspected cases of bovine viral diarrhoea with severe disease in cattle were noticed in farmers' small holdings in Tamil Nadu State. To determine the extent of pestivirus infection, blood, serum, nasal or oral swab samples of 46 cattle from 18 villages were tested. Based on the real‐time RT‐PCR, antigen ELISA and nucleotide sequencing results, pestivirus was detected in nine cattle from eight villages in two districts and all pestiviruses were identified as HoBiPeV. All nine HoBiPeV‐infected cattle displayed clinical signs resembling MD and HoBiPeV isolates (n = 9) obtained were characterized at genetic and antigenic level. Phylogenetic analyses based on 5′‐untranslated regions (5′‐UTR), Npro and combined 5′‐UTR‐Npro gene sequences revealed that eight HoBiPeV isolates clustered into a clade, distinct from all reported HoBiPeV clades (a–d), whereas one belonged to HoBiPeV‐d clade, thus providing evidence of emergence of a novel HoBiPeV clade (e). This was also supported by HoBiPeV‐e clade‐specific amino acid substitutions in Npro and the antigenic reactivity patterns. The study demonstrates the existence and independent evolution of five HoBiPeV clades (four main clades) globally and surprisingly three exclusive to India. Also we confirm first HoBiPeV occurrence in southern India with predominant prevalence of HoBiPeV‐e strains. Besides demonstrating increased HoBiPeV genetic diversity, here we show association of HoBiPeV with severe clinical disease involving fatalities highlighting impact of HoBiPeV on cattle health. The emergence of a novel HoBiPeV lineage provides new insights on global HoBiPeV epidemiology and genetic diversity reiterating the need for continuous monitoring of HoBiPeV in India. [ABSTRACT FROM AUTHOR]

The aim of this article is to express envelope glycoprotein E2 of bovine viral diarrhea virus (BVDV) in yeastPichia pastorisand its utility as a diagnostic antigen in ELISA. The BVDV E2 gene was cloned into the pPICZαA vector followed by integration into thePichia pastorisstrain X-33 genome for methanol-induced expression. SDS-PAGE and Western blot results showed that the recombinant BVDV E2 protein (72 kDa) was expressed and secreted into the medium at a concentration of 40 mg/L of culture under optimized conditions. An indirect ELISA was then developed by using the yeast-expressed E2 protein. Preliminary testing of 300 field cattle serum samples showed that the E2 ELISA showed a sensitivity of 91.07% and a specificity of 92.02% compared to the reference virus neutralization test. The concordance between the E2 ELISA and VNT was 91.67%. This study demonstrates feasibility of BVDV E2 protein expression in yeastPichia pastorisfor the first time and its efficacy as an antigen in ELISA for detecting BVDV neutralizing antibodies in cattle. [ABSTRACT FROM AUTHOR]

The aim of this study was to develop an indirect ELISA using the helicase domain of bovine viral diarrhoea virus (BVDV) NS3 protein instead of full-length NS3 protein for detection of BVDV and BDV antibodies in sheep and goats and its validation by comparing its sensitivity and specificity with virus neutralization test (VNT) as the reference test. The purified 50 kDa recombinant NS3 protein was used as the coating antigen in the ELISA. The optimal concentration of antigen was 320 ng/well at a serum dilution of 1:20 and the optimal positive cut-off optical density value was 0.40 based on test results of 418 VNT negative sheep and goat sera samples. When 569 serum samples from sheep (463) and goats (106) were tested, the ELISA showed a sensitivity of 91.71% and specificity of 94.59% with BVDV VNT. A good correlation (93.67%) was observed between the two tests. It showed a sensitivity of 85% and specificity of 86.6% with VNT in detecting BDV antibody positive or negative samples. This study demonstrates the efficacy of truncated recombinant NS3 antigen based ELISA for seroepidemiological study of pestivirus infection in sheep and goats. [ABSTRACT FROM PUBLISHER]