High mortality in free-ranging wild boars associated with African swine fever virus in India.

The present study focuses on the pathological and molecular characterization of African swine fever virus (ASFV) associated with an outbreak in wild boars in two national parks in southern India in 2022-2023. Significant mortality was observed among free-ranging wild boars at Bandipur National Park, Karnataka, and Mudumalai National Park, Tamil Nadu. Extensive combing operations were undertaken in both national parks, spanning an area of around 100 km2, originating from the reported epicenter, to estimate the mortality rate. Recovered carcasses were pathologically examined, and ASFV isolates was genetically characterized. Our findings suggested spillover infection of ASFV from nearby domestic pigs, and the virus was equally pathogenic in wild boars and domestic pigs. ASFV intrusion was reported in the Northeastern region of the country, which borders China and Myanmar, whereas the current outbreak is very distantly located, in southern India. Molecular data will help in tracing the spread of the virus in the country.

Pathomolecular epidemiology, antimicrobial resistance, and virulence genes of Streptococcus dysgalactiae subsp. equisimilis isolates from slaughtered pigs in India.

AIMS: We aimed to investigate the prevalence, pathology, and characterization of Streptococcus dysgalactiae subsp. equisimilis (SDSE) in slaughtered pigs of India. METHODS AND RESULTS: We collected 1254 morbid tissues (lungs-627 and spleen-627) and 627 heart-blood from 627 slaughtered pigs. The bacterial isolation, antibiogram, virulence gene profiling, and mouse pathogenicity testing were performed for the detection and characterization of SDSE. A total of 177 isolates (heart-blood-160 and tissues-17) were recovered from 627 slaughtered pigs with higher isolation rate in heart-blood (25.51%). The prevalence of SDSE was 11% in morbid tissues by polymerase chain reaction. Majority of isolates showed higher detection of streptolysin O, followed by streptokinase and extracellular phospholipase A virulence genes with higher degree of resistance to azithromycin, clindamycin, erythromycin, and penicillin antibiotics. Mouse pathogenicity testing confirmed virulence based on histopathological lesions and re-isolation of SDSE. CONCLUSIONS: Our findings highlight the high prevalence of SDSE in slaughtered pigs. The presence of virulence genes and mouse pathogenicity testing confirm their pathogenic potential.

Preliminary investigation reveals novel pathological consequences of bluetongue virus-1 infection in the endocrine glands of pregnant Indian sheep.

Bluetongue virus (BTV), a major peril to the sheep industry, infects a wide range of the cells in the infected animals including mononuclear, dendritic and epithelial cells. However, little is known about its tropism for the secretory epithelial cells of endocrine glands and the pathogenesis it induces. The aim of the study was to assess the BTV load, antigen distribution in the tissue of the pituitary, thyroid as well as adrenal glands and associated histopathological consequences. BTV antigens were localized using immunohistochemistry in the thyroid's epithelial cells, zona fasciculata and zona reticularis cells and the anterior pituitary epithelial cells. The real-time PCR portrayed the high viral load in adrenals at 7th days postinoculation (DPI) and in thyroid and pituitary glands at 15th DPI. Serum examination revealed variation in the T-3 and T-4 of infected animals in comparison to the control group. Caspase-3 immunolocalization revealed BTV-1 induces apoptosis in the affected cells of endocrine gland of infected animals. Further, this study signifies the tropism of BTV in the novel sites (endocrine glands) of the host that might be one of the reasons for the poor performance of infected animals.

Evaluation of Stem Cell Laden Collagen + Polycaprolactone + Multi-Walled Carbon Nano-Tubes Nano-Neural Scaffold with and Without Insulin Like Growth Factor-I For Sciatic Nerve Regeneration Post Crush Injury in Wistar Rats.

BACKGROUND/AIMS: All body functions are activated, synchronized and controlled by a substantial, complex network, the nervous system. Upon injury, pathophysiology of the nerve injury proceeds through different paths. The axon may undergo a degenerative retraction from the site of injury for a short distance unless the injury is near to the cell body, in which case it continues to the soma and undergoes retrograde neuronal degeneration. Otherwise, the distal section suffers from Wallerian degeneration, which is marked by axonal swelling, spheroids, and cytoskeleton degeneration. The objective of the study was to evaluate the potential of mesenchymal stem cell laden neural scaffold and insulin-like growth factor I (IGF-I) in nerve regeneration following sciatic nerve injury in a rat model. METHODS: The animals were anaesthetized and a cranio-lateral incision over left thigh was made. Sciatic nerve was exposed and crush injury was introduced for 90 seconds using haemostat at second locking position. The muscle and skin were sutured in routine fashion and thus the rat model of sciatic crush injury was prepared. The animal models were equally distributed into 5 different groups namely A, B, C, D and E and treated with phosphate buffer saline (PBS), carbon nanotubes based neural scaffold only, scaffold with IGF-I, stem cell laden scaffold and stem cell laden scaffold with IGF-I respectively. In vitro scaffold testing was performed. The nerve regeneration was assessed based on physico-neuronal, biochemical, histopathological examination, and relative expression of NRP-1, NRP-2 and GAP-43 and scanning electron microscopy. RESULTS: Sciatic nerve injury model with crush injury produced for 90 seconds was standardized and successfully used in this study. All the biochemical parameters were in normal range in all the groups indicating no scaffold related changes. Physico-neuronal, histopathological, relative gene expression and scanning electron microscopy observations revealed appreciable nerve regeneration in groups E and D, followed by C and B. Restricted to no regeneration was observed in group A. CONCLUSION: Carbon nanotubes based scaffold provided electro-conductivity for proper neuronal regeneration while rat bone marrow-derived mesenchymal stem cells were found to induce axonal sprouting, cellular transformation; whereas IGF-I induced stem cell differentiation, myelin synthesis, angiogenesis and muscle differentiation.

A retrospective study showing a high rate of seropositivity against SARS-CoV-2 in wild felines in India.

We report a high rate of seropositivity against SARS-CoV-2 in wild felines in India. Seropositivity was determined by microneutralization and plaque reduction neutralization assays in captive Asiatic lions, leopards, and Bengal tigers. The rate of seropositivity was positively correlated with that of the incidence in humans, suggesting the occurrence of large spillover events.

Development and evaluation of recombinant gD protein based ELISA for sero-surveillance of BoHV-1 in India.

Bovine herpes virus-1 (BoHV-1) is responsible for production losses through decreased milk yields, abortions, infertility, and trade restrictions in the bovine population. The disease is endemic in many countries including India. As the virus harbors a unique feature of latency animals once infected with the virus remain sero-positive for lifetime and can re-excrete the virus when exposed to stressful conditions. Hence, identification and culling of infected animals is only the means to minimize infection-associated losses. In this study, an economical indigenous assay for the detection of BoHV-1 specific antibodies was developed to cater to the huge bovine population of the country. The viral structural gD protein, expressed in the prokaryotic system was used for optimization of an indirect ELISA for bovines followed by statistical validation of the assay. The diagnostic sensitivity and specificity of the indirect ELISA were 82.9% and 91.3% respectively. Systematically collected serum samples representing organized, unorganized and breeding farms of India were tested with the indigenously developed assay for further validation.

Evaluation of bone marrow-derived mesenchymal stem cells with eggshell membrane for full-thickness wound healing in a rabbit model.

Biomaterials capable of managing wounds should have essential features like providing a natural microenvironment for wound healing and as support material for stimulating tissue growth. Eggshell membrane (ESM) is a highly produced global waste due to increased egg consumption. The unique and fascinating properties of ESM allow their potential application in tissue regeneration. The wound healing capacity of bone marrow-derived mesenchymal stem cells (BM-MSCs), ESM, and their combination in rabbits with full-thickness skin defect (2 × 2 cm2) was evaluated. Twenty-five clinically healthy New Zealand White rabbits were divided into five groups of five animals each, with group A receiving no treatment (control group), group B receiving only fibrin glue (FG), group C receiving FG and ESM as a dressing, group D receiving FG and BM-MSCs, and group E receiving a combination of FG, ESM, and BM-MSCs. Wound healing was assessed using clinical, macroscopical, photographic, histological, histochemical, hematological, and biochemical analysis. Macroscopic examination of wounds revealed that healing was exceptional in group E, followed by groups D and C, compared to the control group. Histopathological findings revealed improved quality and a faster rate of healing in group E compared to groups A and B. In addition, healing in group B treated with topical FG alone was nearly identical to that in control group A. However, groups C and D showed improved and faster recovery than control groups A and B. The macroscopic, photographic, histological, and histochemical evaluations revealed that the combined use of BM-MSCs, ESM, and FG had superior and faster healing than the other groups.

Molecular epidemiological studies on avian pathogenic Escherichia coli associated with septicemia in chickens in India.

Bacterial septicemia causes huge economic losses in the poultry industry and there is no systematic research available in India on the connection of various pathogens associated with septicemia. The present molecular epidemiological study was conducted to investigate the association of different bacterial and immunosuppressive viral pathogens in septicemia suspected chickens. A total of 443 chicken carcasses with septicemic conditions from 71 different flocks were included in this study. Heart blood swabs were subjected to bacterial culture for Salmonella spp., Pasteurella multocida, Escherichia coli, and Gallibacterium anatis. Of these 51 flocks tested for E. coli, 49 (96.1%) flocks were found positive. Among flocks tested for Salmonella spp., 2 flocks were found positive. All tested flocks were found negative for G. anatis and P. multocida as well as air sac swabs tested negative for Mycoplasma spp. Bacterial cultural examination revealed that majority of septicemic chickens were found to be infected with E. coli and these E. coli isolates showed the highest resistance to vancomycin (60%), followed by erythromycin (50%) and cefotaxime (38%) and maximum sensitivity to cefotaxime and clavulanic acid combinations (81.5%), followed by chloramphenicol (69.6%) and ertapenem (67.2%). Among the 5 avian pathogenic E. coli (APEC) virulence genes were detected in 36 flocks and highest frequency of iss (100%), followed by ompT or iutA (97.2%), hly (61.1%) and iroN (47.2%) genes. On polymerase chain reaction (PCR) screening, 10.5, 4.5, 52.2, 19.4, 9.0, 4.5, 20.1 and 19.4% of the flocks were positive for G. anatis, Ornithobacterium rhinotracheale, APEC, Salmonella spp., Mycoplasma gallisepticum, Mycoplasma synoviae, chicken infectious anemia virus and Marek's disease virus, respectively. To our knowledge, the present study is first on the etiology of septicemia in chicken flocks in India. The present study infers that the majority of septicemic deaths in broiler chickens less than 8 weeks have been connected with APEC and majority of E. coli isolates are multidrug resistance, suggesting the need for surveillance and intervention to curb the inadvertent use of antibiotics. Although, incidence of G. anatis association with septicemia was reported, still requires a rigorous epidemiological study to determine the actual prevalence. However, more detailed studies encompassing vast geographical area with large sample size and long duration of the studies are necessary to provide a clear picture of the interaction of different pathogens causing septicemia in chicken.

Coronavirus Disease 2019-COVID-19.

SUMMARYIn recent decades, several new diseases have emerged in different geographical areas, with pathogens including Ebola virus, Zika virus, Nipah virus, and coronaviruses (CoVs). Recently, a new type of viral infection emerged in Wuhan City, China, and initial genomic sequencing data of this virus do not match with previously sequenced CoVs, suggesting a novel CoV strain (2019-nCoV), which has now been termed severe acute respiratory syndrome CoV-2 (SARS-CoV-2). Although coronavirus disease 2019 (COVID-19) is suspected to originate from an animal host (zoonotic origin) followed by human-to-human transmission, the possibility of other routes should not be ruled out. Compared to diseases caused by previously known human CoVs, COVID-19 shows less severe pathogenesis but higher transmission competence, as is evident from the continuously increasing number of confirmed cases globally. Compared to other emerging viruses, such as Ebola virus, avian H7N9, SARS-CoV, and Middle East respiratory syndrome coronavirus (MERS-CoV), SARS-CoV-2 has shown relatively low pathogenicity and moderate transmissibility. Codon usage studies suggest that this novel virus has been transferred from an animal source, such as bats. Early diagnosis by real-time PCR and next-generation sequencing has facilitated the identification of the pathogen at an early stage. Since no antiviral drug or vaccine exists to treat or prevent SARS-CoV-2, potential therapeutic strategies that are currently being evaluated predominantly stem from previous experience with treating SARS-CoV, MERS-CoV, and other emerging viral diseases. In this review, we address epidemiological, diagnostic, clinical, and therapeutic aspects, including perspectives of vaccines and preventive measures that have already been globally recommended to counter this pandemic virus.

Detection of SARS-CoV-2 in a free ranging leopard (Panthera pardus fusca) in India.

We report an incidence of natural infection of SARS-CoV-2 in free-ranging Indian leopard (Panthera pardus fusca). The case was detected during routine screening. Post-mortem and laboratory examination suggested virus-induced interstitial pneumonia. Viral genome could be detected in various organs including brain, lung, spleen, and lymph nodes by real-time PCR. Whole-genome sequence analysis confirmed infection of Pango lineage B.1.617.2 of SARS-CoV-2. Till now, only Asiatic lions have been reported to be infected by SARS-CoV-2 in India. Infections in animals were detected during peak phase of pandemic and all the cases were captive with close contacts with humans, whereas the present case was observed when human cases were significantly low. No tangible evidence linked to widespread infection in the wild population and the incidence seems to be isolated case. High nucleotide sequence homology with prevailing viruses in humans suggested spillover infection to the animal. This report underlines the need for intensive screening of wild animals for keeping track of the virus evolution and development of carrier status of SARS-CoV-2 among wildlife species. Supplementary Information: The online version contains supplementary material available at 10.1007/s10344-022-01608-4.

First description of natural concomitant infection of avian nephritis virus and infectious bronchitis virus reveals exacerbated inflammatory response and renal damage in broiler chicks.

We describe the first report on spontaneous Avian Nephritis Virus (ANV) and Infectious Bronchitis Virus (IBV) concurrent infection in broiler chicks. On necropsy, the kidneys were found swollen with its parenchyma and ureters stuffed with urate flakes. Histopathologically, the renal tubular damage and inflammatory response were severe in concurrently infected birds compared to the cases infected only with ANV, which had direct correlation with significantly (p < 0.001) increased expression of IL-1 ß, IL-4, IL-12, IL-13, iNOS and IFN-γ transcripts in the kidneys of concurrently infected birds. Relative decrease in IFN-ß transcript levels in the concurrently infected birds indicates suppression of antiviral response; the iNOS level was manifold increased which can be attributed to the enhanced macrophage response. Nucleotide sequencing of S1-spike glycoprotein gene of IBV and RNA dependent RNA polymerase gene of ANV confirmed etiologies as Igacovirus of Gammacoronavirus and ANV-2 of Avastrovirus 2, respectively. Both ANV and IBV virus affect kidneys. Our findings suggested that concurrent infections of these two viruses might have enhanced the transcripts of Th1, Th2 and proinflammatory cytokines with reduced IFN-ß transcripts resulting in decreased host innate antiviral mechanisms leading to exacerbated renal lesions. Future experimental co-infection studies could throw more lights on pathology and pathogenesis during concurrent infections of ANV and IBV in poultry.

Development of BruAb2_0168 based isothermal polymerase spiral reaction assay for specific detection of Brucella abortus in clinical samples.

Bovine brucellosis, predominantly caused by Brucella abortus is one of the most neglected zoonotic diseases causing severe economic losses in the dairy industry. The early and precise diagnosis of the disease is required to reduce the transmission of infection in humans as well as animals. In the current study, a rapid and novel isothermal amplification-based polymerase spiral reaction (PSR) was developed for the specific detection of Brucella abortus by targeting the BruAb2_0168 gene. The assay could be conducted at 65 °C in a water bath and results can be obtained after 60 min. The detection limit of the PSR assay was found to be 1.33 fg. The sensitivity of the assay was found to be 104 fold higher than conventional PCR and equivalent to real-time PCR (RT-PCR). The assay didn't exhibit cross-reaction with selected pathogenic non-Brucella bacteria and Brucella spp. other than B. abortus. Forty clinical samples were also tested using this novel assay and it was able to detect 25 samples as positive, however, conventional PCR could detect the targeted organism in 22 samples only. To the extent of our knowledge, this is the first report towards the development of a PSR assay for specific detection of B. abortus. The assay can be used as a quick, sensitive and accurate test for the diagnosis of bovine brucellosis in the field setting. Relatively one of the paradigm-shifting aspects of this assay would be it does not require any expensive equipment and the results can be easily visualized by the unaided eye, therefore making PSR a valuable diagnostic tool in field conditions.

Genetic and phylogenetic characterization of polycistronic dsRNA segment-10 of bluetongue virus isolates from India between 1985 and 2011.

The smallest polycistronic dsRNA segment-10 (S10) of bluetongue virus (BTV) encodes NS3/3A and putative NS5. The S10 sequence data of 46 Indian BTV field isolates obtained between 1985 and 2011 were determined and compared with the cognate sequences of global BTV strains. The largest ORF on S10 encodes NS3 (229 aa) and an amino-terminal truncated form of the protein (NS3A) and a putative NS5 (50-59 aa) due to alternate translation initiation site. The overall mean distance of the global NS3 was 0.1106 and 0.0269 at nt and deduced aa sequence, respectively. The global BTV strains formed four major clusters. The major cluster of Indian BTV strains was closely related to the viruses reported from Australia and China. A minor sub-cluster of Indian BTV strains were closely related to the USA strains and a few of the Indian strains were similar to the South African reference and vaccine strains. The global trait association of phylogenetic structure indicates the evolution of the global BTV S10 was not homogenous but rather represents a moderate level of geographical divergence. There was no evidence of an association between the virus and the host species, suggesting a random spread of the viruses. Conflicting selection pressure on the alternate coding sequences of the S10 was evident where NS3/3A might have evolved through strong purifying (negative) selection and NS5 through a positive selection. The presence of multiple positively selected codons on the putative NS5 may be advantageous for adaptation of the virus though their precise role is unknown.

Decellularization of Skin Tissue.

Biomaterials science encompasses elements of medicine, biology, chemistry, materials, and tissue engineering. They are engineered to interact with biological systems to treat, augment, repair, or replace lost tissue function. The choice of biomaterial depends on the procedure being performed, the severity of the patient's condition, and the surgeon's preference. Prostheses made from natural-derived biomaterials are often derived from decellularized extracellular matrix (ECM) of animal (xenograft) or human (allograft) origin. Advantages of using ECM include their resemblance in morphology and three-dimensional structures with that of tissue to be replaced. Due to this, scientists all over are now focusing on naturally derived biomaterials which have been shown to possess several advantages compared to synthetic ones, owing to their biocompatibility, biodegradability, and remodeling properties. Advantages of a naturally derived biomaterial enhance their application for replacement or restoration of damaged organs/tissues. They adequately support cell adhesion, migration, proliferation, and differentiation. Naturally derived biomaterials can induce extracellular matrix formation and tissue repair when implanted into a defect by enhancing attachment and migration of cells from surrounding environment. In the current chapter, we will focus on the natural and synthetic dermal matrix development and all of the progress in this field.

SARS-CoV-2 existence in sewage and wastewater: A global public health concern?

The SARS-CoV-2/COVID-19 pandemic has spread across the globe and affected millions of individuals as of the efficient virus transmission potential mediated via multiple virus shedding routes. The presence of SARS-CoV-2 in the stool samples and its prolonged shedding in environmental compartments like sewage and wastewater signifies a potential threat adding to the transmission cycle of this novel virus. The potential role played by the asymptomatic COVID-19 patients in transmitting the disease via the fecal-oral route is now under investigation. Hence, in the present scenario, wastewater-based epidemiology, and sewage surveillance may provide valuable insights into the prevalence of SARS-CoV-2 among the human population and could serve as a sensitive surveillance system and a crucial early warning tool. Further studies are required to determine the survival of SARS-CoV-2 in the environment, transmissibility through wastewater, and the potential to infect humans via the fecal-oral route. Appropriate frameworks with regards to evaluation and analysis of SARS-CoV-2 will help implement appropriate intervention strategies and necessary sanitation practices to ensure virus free clean water supply to have a check on the further spread of this pandemic virus.

Immunofluorescence and molecular diagnosis of bovine respiratory syncytial virus and bovine parainfluenza virus in the naturally infected young cattle and buffaloes from India.

Pneumonia in bovines is a multifactorial disease manifestation leading to heavy economic losses. Infections of bovine respiratory syncytial virus (BRSV) and bovine parainfluenza virus-3 (BPI-3) are among the important contributing factors for the development of pneumonia in young animals. These viral agents either primarily cause pneumonia or predispose animals to the development of pneumonia. Although, the role of BRSV and BPI-3 in the pathogenesis of pneumonia is well established, there are no reports of involvement of BRSV and BPI-3 from Indian cattle and buffaloes suffering from pneumonia. In the present investigation, we performed postmortem examinations of 406 cattle and buffaloes, which were below twelve months of age. Out of 406 cases, twelve (2.95%) cases were positive for BRSV and fifteen (3.69%) cases were positive for BPI-3, screened by reverse transcriptase polymerase chain reaction (RT-PCR). Further, positive cases were confirmed by sequence analysis of RT-PCR amplicons and direct immunofluorescence antibody test (d-FAT) in paraffin-embedded lung tissue sections. BRSV positive cases revealed characteristic findings of bronchiolar epithelial necrosis, thickened alveolar septa by mononuclear cells infiltration and edema; alveolar lumens were filled with mononuclear cells and numerous syncytial cells were seen having intracytoplasmic inclusions. The BRSV antigen distribution was found to be in bronchiolar and alveolar epithelium and syncytial cells in the lung sections. In fifteen cases, where BPI-3 was detected, bronchointerstitial pneumonia in the majority of cases with thickened alveolar septa by mild macrophage infiltration, hyperplasia of type-II pneumocytes and bronchiolar necrosis along with syncytial cells having intracytoplasmic inclusions in the majority of cases were observed. The BPI-3 antigen distribution was found to be in bronchiolar and alveolar epithelium and syncytial cells in the lung sections. RT-PCR amplicons of BRSV and BPI-3 obtained were sequenced and their analysis showed homology with already available sequences in the NCBI database. It is the first report of detection of BRSV and BPI-3 from pneumonic cases by RT-PCR and d-FAT from cattle and buffaloes of India, indicating the need for more epidemiological studies.

VP2 Gene-Based Molecular Evolutionary Patterns of Major Circulating Bluetongue Virus Serotypes Isolated during 2014-2018 from Telangana and Andhra Pradesh States of India.

INTRODUCTION: Bluetongue disease is an economically important viral disease of livestock caused by bluetongue virus (BTV) having multiple serotypes. It belongs to the genus Orbivirus of family Reoviridae and subfamily Sedoreovirinae. The genome of BTV is 10 segmented dsRNA that codes for 7 structural and 4 nonstructural proteins, of which VP2 was reported to be serotype-specific and a major antigenic determinant. OBJECTIVE: It is important to know the circulating serotypes in a particular geographical location for effective control of the disease. The present study unravels the molecular evolution of the circulating BTV serotypes during 2014-2018 in Telangana and Andhra Pradesh states of India. METHODS: Multiple sequence alignment with available BTV serotypes in GenBank and phylogenetic analysis were performed for the partial VP2 sequences of major circulating BTV serotypes during the study period. RESULTS: The multiple sequence alignment of circulating serotypes with respective reference isolates revealed variations in antigenic VP2. The phylogenetic analysis revealed that the major circulating serotypes were grouped into eastern topotypes (BTV-1, BTV-2, BTV-4, and BTV-16) and Western topotypes (BTV-5, BTV-12, and BTV-24). CONCLUSION: Our study strengthens the need for development of an effective vaccine, which can induce the immune response for a range of serotypes within and in between topotypes.

SARS-CoV-2/COVID-19 and advances in developing potential therapeutics and vaccines to counter this emerging pandemic.

A novel coronavirus (SARS-CoV-2), causing an emerging coronavirus disease (COVID-19), first detected in Wuhan City, Hubei Province, China, which has taken a catastrophic turn with high toll rates in China and subsequently spreading across the globe. The rapid spread of this virus to more than 210 countries while affecting more than 25 million people and causing more than 843,000 human deaths, it has resulted in a pandemic situation in the world. The SARS-CoV-2 virus belongs to the genus Betacoronavirus, like MERS-CoV and SARS-CoV, all of which originated in bats. It is highly contagious, causing symptoms like fever, dyspnea, asthenia and pneumonia, thrombocytopenia, and the severely infected patients succumb to the disease. Coronaviruses (CoVs) among all known RNA viruses have the largest genomes ranging from 26 to 32 kb in length. Extensive research has been conducted to understand the molecular basis of the SARS-CoV-2 infection and evolution, develop effective therapeutics, antiviral drugs, and vaccines, and to design rapid and confirmatory viral diagnostics as well as adopt appropriate prevention and control strategies. To date, August 30, 2020, no effective, proven therapeutic antibodies or specific drugs, and vaccines have turned up. In this review article, we describe the underlying molecular organization and phylogenetic analysis of the coronaviruses, including the SARS-CoV-2, and recent advances in diagnosis and vaccine development in brief and focusing mainly on developing potential therapeutic options that can be explored to manage this pandemic virus infection, which would help in valid countering of COVID-19.

Inhibition of MEK-ERK1/2-MAP kinase signalling pathway reduces rabies virus induced pathologies in mouse model.

The extracellular signal-regulated kinase (ERK) pathway has been shown to regulate pathogenesis of many viral infections, but its role during rabies virus (RV) infection in vivo is not clear. In the present study, we investigated the potential role of MEK-ERK1/2 signalling pathway in the pathogenesis of rabies in mouse model and its regulatory effects on pro-inflammatory cytokines and other mediators of immunity, and kinetics of immune cells. Mice were infected with 25 LD50 of challenge virus standard (CVS) strain of RV by intracerebral (i.c.) inoculation and were treated i.c. with U0126 (specific inhibitor of MEK1/2) at 10 µM/mouse at 0, 2, 4 and 6 days post-infection. Treatment with U0126 resulted in delayed disease development and clinical signs, increased survival time with lesser mortality than untreated mice. The better survival of inhibitor-treated and RV infected mice was positively correlated with reduced viral load and reduced viral spread in the brain as quantified by real-time PCR, direct fluorescent antibody test and immunohistochemistry. CVS-infected/mock-treated mice developed severe histopathological lesions with increased Fluoro-Jade B positive degenerating neurons in brain, which were associated with higher levels of serum nitric oxide, iNOS, TNF-α, and CXCL10 mRNA. Also CVS-infected/U0126-treated mice revealed significant decrease in caspase 3 but increase in Bcl-2 mRNA levels and less TUNEL positive apoptotic cells. CVS-infected/U0126-treated group also showed significant increase in CD4+, CD8+ T lymphocytes and NK cells in blood and spleen possibly due to less apoptosis of these cells. In conclusion, these data suggest that MEK-ERK1/2 signalling pathway play critical role in the pathogenesis of RV infection in vivo and opens up new avenues of therapeutics.

Pathological, immunological and molecular epidemiological analysis of lumpy skin disease virus in Indian cattle during a high-mortality epidemic.

Lumpy skin disease (LSD) is an economically significant, emerging viral disease of Cattle and Buffaloes. This study aimed to investigate the causes of high mortality in a recent LSD epidemic in India. We examined 1618 animals across seventy outbreaks and conducted post-mortem on 48 cattle out of 513 clinically suspected LSD cases. The morbidity, mortality and case fatality rates recorded were 31.70%, 2.97 and 9.37% respectively. Disease stages were categorized as early (20.81%), mid (42.02%), and late (37.17%) and the distribution of skin lesions was classified as mild (34.14%), moderate (39.39%), and severe (26.47%). Post-mortem findings revealed systemic infection with necrotic and ulcerative nodules on multiple internal organs. Histologically, necrotizing vasculitis and mononuclear cell infiltration with intracytoplasmic inclusions were observed in various organs. The highest viral load was found in skin nodules/scabs, trachea, tongue, and lymph nodes. The viral load was significantly higher in mid- and late-stages of skin nodules and internal organs; whereas, blood from early-stage showed high viral load. The expression of Th1-type and Th2-type cytokines varied significantly across different stages of the disease. The downregulation of the apoptotic intrinsic and upregulation of the extrinsic pathway genes, suggesting that the latter plays a role in LSDV infection. Genetic analysis revealed that the LSD virus (LSDV) isolates were derived from a Kenyan ancestral strain with unique nucleotide changes in RPO30 and P32 gene. In conclusion, the high mortality in the recent Indian LSD epidemic can be attributed to a newly identified, highly virulent strain of LSDV causing systemic infection.