Bluetongue virus: Past, present, and future scope.

Bluetongue (BT), once considered a disease of sheep confined to the southern African region, has spread all over the world. BT is a viral disease caused by the bluetongue virus (BTV). BT is regarded as an economically important disease in ruminants of compulsory notification to OIE. BTV is transmitted by the bite of Culicoides species. Research over the years has led to a better understanding of the disease, the nature of the virus life cycle between ruminants and Culicoides species, and its distribution in different geographical regions. Advances have also been made in understanding the molecular structure and function of the virus, the biology of the Culicoides species, its ability to transmit the disease, and the persistence of the virus inside the Culicoides and the mammalian hosts. Global climate change has enabled the colonization of new habitats and the spread of the virus into additional species of the Culicoides vector. This review highlights some of the current findings on the status of BT in the world based on the latest research on disease aspects, virus-host-vector interactions, and the different diagnostic approaches and control strategies available for BTV.

Biochemistry, Synthesis, and Applications of Bacterial Cellulose: A Review.

The potential of cellulose nanocomposites in the new-generation super-performing nanomaterials is huge, primarily in medical and environment sectors, and secondarily in food, paper, and cosmetic sectors. Despite substantial illumination on the molecular aspects of cellulose synthesis, various process features, namely, cellular export of the nascent polysaccharide chain and arrangement of cellulose fibrils into a quasi-crystalline configuration, remain obscure. To unleash its full potential, current knowledge on nanocellulose dispersion and disintegration of the fibrillar network and the organic/polymer chemistry needs expansion. Bacterial cellulose biosynthesis mechanism for scaled-up production, namely, the kinetics, pathogenicity, production cost, and product quality/consistency remain poorly understood. The bottom-up bacterial cellulose synthesis approach makes it an interesting area for still wider and promising high-end applications, primarily due to the nanosynthesis mechanism involved and the purity of the cellulose. This study attempts to identify the knowledge gap and potential wider applications of bacterial cellulose and bacterial nanocellulose. This review also highlights the manufacture of bacterial cellulose through low-cost substrates, that is, mainly waste from brewing, agriculture, food, and sugar industries as well as textile, lignocellulosic biorefineries, and pulp mills.

Virus as a Nanocarrier for Drug Delivery Redefining Medical Therapeutics - A Status Report.

Over the last two decades, drug delivery systems have evolved at a tremendous pace. Synthetic nanoparticles have played an important role in vaccine design and delivery as these have shown improved safety and efficacy over conventional formulations. Nanocarriers formulated by natural, biological building blocks have become an important tool in biomedicine. A successful nanocarrier must possess specific properties like evading the host immune system, target specificity, cellular entry, escape from endosomes, and the ability to release the active material into the cytoplasm. The virus can perform some or all of these functions, making it a suitable candidate as a naturally occurring nanocarrier. Viruses could be made non-infectious and non-replicative without compromising their ability to penetrate cells, making them useful for a vast spectrum of applications. Currently, many such carrier molecules as bio-nanocapsules are at various development stages. This review covers the advances in the field of viruses as potential nanocarriers and discusses the related technologies and strategies to target specific cells by using virus-inspired nanocarriers. These virus-based nanocarriers could provide solutions to address pressing and emerging concerns in infectious diseases in the future.

Two novel genomic DNA sequences as common diagnostic targets to detect Cryptosporidium hominis and Cryptosporidium parvum: Development of quantitative polymerase chain reaction assays, and clinical evaluation.

Introduction: Cryptosporidium is an intestinal parasite responsible for gastroenteritis. Conventional diagnosis of Cryptosporidium is made by microscopy. The most frequent molecular detection method for this parasite is polymerase chain reaction (PCR). The objective of the present study was to identify the novel DNA targets and development of PCR-based assays for the specific detection of two major human infecting species Cryptosporidium parvum and Cryptosporidium hominis. Methodology: Sensitive and specific SYBR green quantitative PCR (qPCR) and TaqMan qPCR assays were developed and validated at both diagnostic and analytical level using the new identified targets TU502HP-1 and TU502HP-2. Results: Assay validation results showed that the newly developed real-time PCR assays are 100% specific with a reliable limit of detection. Overall repeatability and reproducibility of these assays showed good quality results over intra- and inter-laboratory analysis. Conclusion: Novel target-based qPCR assays can be rapid an efficient tool for simultaneous detection of a C. parvum and C. hominis. These genes could also be utilized for the development of innovative DNA-based Point-of-Care test development.

Major enteropathogens in humans, domestic animals, and environmental soil samples from the same locality: prevalence and transmission considerations in coastal Odisha, India.

OBJECTIVES: Regions with limited sanitation facilities have higher rates of infections with various enteric pathogens. It is therefore important to identify different hosts and their relative contribution to pathogen shedding into the environment, and to assess the subsequent health risks to humans. METHODS: In this study, human faecal (n=310), animal faecal (n=150), and environmental (soil) samples (n=40) were collected from the same locality and screened for selected enteric pathogens by immunochromatography and/or polymerase chain reaction. RESULTS: At least 1 microbial agent was detected in 49.0%, 44.7%, and 40.0% of the samples from human, animals, and soil, respectively. Among humans, rotavirus was predominantly detected (17.4%) followed by enteropathogenic Escherichia coli (EPEC) (15.4%), Shigella (13.8), and Shiga toxin-producing E. coli (STEC) (9.7%). Among animals, STEC was detected most frequently (28.0%), and EPEC was the major enteric pathogen detected in soil (30.0%). The detection rate of rotavirus was higher among younger children (≤2 years) than among older children. Single infections were more commonly detected than multiple infections in humans (p<0.01), unlike the observations in animal and soil samples. For diarrhoeagenic E. coli and Shigella, most of the human and animal isolates showed close relatedness, suggesting possible cross-infection between humans and domesticated animals in the area studied. CONCLUSIONS: The present study provides an improved understanding of the distribution of major enteric pathogens coexisting in humans and animals in the region, thereby suggesting a high potential for possible transmission among livestock and communities residing in the studied locality.

Detection and molecular typing of campylobacter isolates from human and animal faeces in coastal belt of Odisha, India.

Introduction: Campylobacter-mediated diarrhoea is one of the major causes of gastroenteritis globally. A majority of the Campylobacter spp. that cause disease in humans have been isolated from animals. Faecal contamination of food and water is the identified frequent cause of human campylobacteriosis. Methodology: In the present study, faecal samples from patients with symptoms of acute diarrhoea (n = 310) and domestic animals including cows (n = 60), sheep (n = 45) and goats (n = 45) were collected from the same localities in the peri-urban Bhubaneswar city. Genomic DNA isolation followed by polymerase chain reaction and sequencing was employed to analyse Campylobacter spp.-positive samples. Results: Of the 460 faecal samples, 16.77% of human samples and 25.33% of animal samples were found to be positive for Campylobacter spp. Among animals, the isolation rate was highest in sheep followed by cows and goats with 9.33%, 8.66% and 7.33%, respectively. The highest number of Campylobacter-positive cases was diagnosed in infants of 2-5 years age. Concurrent infection of other pathogens in addition to Campylobacter spp. was frequently detected in the samples. Conclusion: The present study showed the incidence of Campylobacter infections in human and different animal species in and around Bhubaneswar, Odisha. The analysis suggested that domestic animals can be the potential sources for human campylobacteriosis in the region.

Epidemiology and phylogenetic analysis of human rhinovirus/Enterovirus in Odisha, Eastern India.

Introduction: Human rhinovirus (HRV) and Enterovirus (ENV) are the major causes of childhood acute respiratory tract infections (ARTIs). This study sought to understand the distribution pattern of HRV subgroups, their seasonality and association with respiratory complications in patients at a tertiary care hospital. Results: Of the total 332 ARTI samples, 82 (24.7%) were positive for ENV/HRV. Twenty positive samples were processed further for phylogenetic analysis. Ten of the 20 samples were identified to be HRVs (70% HRV A and 30% HRV C) and nine were enteroviruses. HRV A clustered near three distinct HRV types (A12, A78 and A82). Four of the HRV strains (represented as SEQ 137 rhino, SEQ 282 rhino, SEQ 120 rhino and SEQ 82 rhino) had high sequence similarity. HRV C showed seasonality and was associated with disease severity. Conclusion: The genotyping and phylogenetic analysis of the HRVs in the current study shows its circulatory pattern, association with risk factors and evolutionary dynamics.

In vitro evaluation of adherence and anti-infective property of probiotic Lactobacillus plantarum DM 69 against Salmonella enterica.

Gastrointestinal infections are a global health problem, and the potential use of probiotic Lactobacillus species to control such infections represents a promising approach. To exert the health benefits on the host, studying the colonization and adherence properties of probiotic bacteria in vitro is crucial. In this context, investigation was carried out to evaluate adhesion, aggregation and anti-infective effect of an indigenous probiotic Lactobacillus plantarum DM 69 against an enteric pathogen Salmonella enterica subsp. enterica ATCC 35640. The results obtained in this study indicated the strong hydrophobic property of the probiotic candidate. In addition, probiotic strain L. plantarum DM 69 also showed higher percentage of self aggregation (58.66%) and low co-aggregation with S. enterica (23.5%). Investigation on antimicrobial property of the probiotic strain revealed its broad-spectrum activity against S. enterica which may have the potential as antibiotics. On analyzing the antimicrobial compound, infrared (IR) spectroscopy indicated the proteinaceous nature of the compound with a molecular weight of 12010.2751 Da. On evaluating the competitive exclusion properties of probiotic strain we observed that L. plantarum DM 69 and its purified antimicrobial compound could control and inhibit pathogen adhesion and penetration into HCT-116 cells. Probiotic L. plantarum DM 69 and its therapeutic properties must be evaluated further.

Co-circulation of all four dengue virus serotypes: First report from Odisha.

The present report describes the detection of co-circulation of all the four dengue serotypes along with rarely detected dengue viruses (DENVs)-4 for the first time in Odisha. One hundred and forty-eight blood samples were tested for dengue NS1 antigen ELISA and IgM antibody (Ab), and twenty early samples were subjected for type-specific multiplex reverse transcription-polymerase chain reaction (RT-PCR). Twenty-three samples found positive for dengue NS1 and/or IgM Ab; five were positive by RT-PCR. DENV-4 was detected in one sample, DENV-2 in two and 2 were co-infected with DENV-1 and 3. Co-circulation of all four dengue serotypes in Eastern India emphasises the need of molecular monitoring of circulating DENV serotypes.

Revisiting the global problem of cryptosporidiosis and recommendations.

Cryptosporidiosis is a gastrointestinal illness caused by the protozoan parasite Cryptosporidium species, which is a leading cause of diarrhea in a variety of vertebrate hosts. The primary mode of transmission is through oral routes; infections spread with the ingestion of oocysts by susceptible animals or humans. In humans, Cryptosporidium infections are commonly found in children and immunocompromised individuals. The small intestine is the most common primary site of infection in humans while extraintestinal cryptosporidiosis occurs in immunocompromised individuals affecting the biliary tract, lungs, or pancreas. Both innate and adaptive immune responses play a critical role in parasite clearance as evident from studies with experimental infection in mice. However, the cellular immune responses induced during human infections are poorly understood. In this article, we review the currently available information with regard to epidemiology, diagnosis, therapeutic interventions, and strategies being used to control cryptosporidiosis infection. Since cryptosporidiosis may spread through zoonotic mode, we emphasis on more epidemiological surveillance-based studies in developing countries with poor sanitation and hygiene. These epidemiological surveys must incorporate fecal source tracking measures to identify animal and human populations contributing significantly to the fecal burden in the community, as mitigation measures differ by host type.

Multiple etiologies of infectious diarrhea and concurrent infections in a pediatric outpatient-based screening study in Odisha, India.

BACKGROUND: There are multiple etiologies responsible for infectious gastroenteritis causing acute diarrhea which are often under diagnosed. Also acute diarrhea is one of the major causes of morbidity and mortality among children less than 5 years of age. METHODS: In our study, fecal samples (n = 130) were collected from children (<5 years) presenting with symptoms of acute diarrhea. Samples were screened for viral, bacterial, and parasitic etiologies. Rotavirus and Adenovirus were screened by immunochromatographic tests. Diarrheagenic Escherichia coli (EPEC, EHEC, STEC, EAEC, O157, O111), Shigella spp., Salmonella spp., Vibrio cholera, Cryptosporidium spp., and Giardia spp. were detected by gene-specific polymerase chain reaction. RESULTS: Escherichia coli was detected to be the major etiological agent (30.07%) followed by Rotavirus (26.15%), Shigella (23.84%), Adenovirus (4.61%), Cryptosporidium (3.07%), and Giardia (0.77%). Concurrent infections with two or more pathogens were observed in 44 of 130 (33.84%) cases with a predominant incidence particularly in <2-year-old children (65.90%) compared to children of 2-5 years age group (34.09%). An overall result showed significantly higher detection rates among children with diarrhea in both combinations of two as well as three infections concurrently (p = 0.004915 and 0.03917, respectively). CONCLUSION: Suspecting possible multiple infectious etiologies and diagnosis of the right causative agent(s) can aid in a better pharmacological management of acute childhood diarrhea. It is hypothesized that in cases with concurrent infections the etiological agents might be complementing each other's strategies of pathogenesis resulting in severe diarrhea that could be studied better in experimental infections.

In silico identification and validation of a novel hypothetical protein in Cryptosporidium hominis and virtual screening of inhibitors as therapeutics.

Computational approaches to predict structure/function and other biological characteristics of proteins are becoming more common in comparison to the traditional methods in drug discovery. Cryptosporidiosis is a major zoonotic diarrheal disease particularly in children, which is caused primarily by Cryptosporidium hominis and Cryptosporidium parvum. Currently, there are no vaccines for cryptosporidiosis and recommended drugs are ineffective. With the availability of complete genome sequence of C. hominis, new targets have been recognized for the development of effective and better drugs and/or vaccines. We identified a unique hypothetical protein (TU502HP) in the C. hominis genome from the CryptoDB database. A three-dimensional model of the protein was generated using the Iterative Threading ASSEmbly Refinement server through an iterative threading method. Functional annotation and phylogenetic study of TU502HP protein revealed similarity with human transportin 3. The model is further subjected to a virtual screening study form the ZINC database compound library using the Dock Blaster server. A docking study through AutoDock software reported N-(3-chlorobenzyl)ethane-1,2-diamine as the best inhibitor in terms of docking score and binding energy. The reliability of the binding mode of the inhibitor is confirmed by a complex molecular dynamics simulation study using GROMACS software for 10 ns in the water environment. Furthermore, antigenic determinants of the protein were determined with the help of DNASTAR software. Our findings report a great potential in order to provide insights in the development of new drug(s) or vaccine(s) for treatment and prophylaxis of cryptosporidiosis among humans and animals.

Etiology, seasonality, and clinical characteristics of respiratory viruses in children with respiratory tract infections in Eastern India (Bhubaneswar, Odisha).

Acute respiratory tract infections (ARTIs) are a leading cause of morbidity and mortality in young children in low and middle income countries. To analyse the overall burden of respiratory viruses responsible for ARTIs in paediatrics population in eastern India, this study was performed. Clinical information, demographic information and nasal/oral swabs were collected from 332 paediatric patients (aged from 1 month to 12 years old) with the symptoms of ARTI, enrolled from the outpatient department from Nov 2012 to Oct 2014. Multiplex PCR was performed to detect eight respiratory viral pathogens. Seasonal, as well as age-wise prevalence of respiratory viruses was analysed. Of these 332 cases, 32.53% (108/332) were positive for at least one pathogen. Human rhinovirus (HRV) was the most frequently detected pathogen (24.7%, 82/332) followed by respiratory syncytial virus (RSV) (4.22%, 14/332), PIV (2.11%, 7/332), and hMPV (2.11%, 7/332). Single infection was detected in 92.6% (100/108) of positive cases. Respiratory virus infections showed seasonal variation, with peaks during the rainy season followed by winter season, and were most common in patients under 1 year of age. Phylogenetic analysis of HMPV positive samples confirmed the circulation of A2 subgroup in the study area. The present study is first of its kind and adds to our knowledge of the epidemiological characteristics of these common respiratory viruses among patients with ARTIs in the study area. J. Med. Virol. 89:553-558, 2017. © 2016 Wiley Periodicals, Inc.

Comparison of bluetongue virus detection and quantitation methods in south India.

INTRODUCTION: Bluetongue (BT), a vector-borne viral disease, primarily affects sheep. Of the 26 serotypes of BTV identified so far, 22 are reported to be circulating in India. Due to an increase in vector population and delays in disease diagnosis, the BT control program heavily relies on rapid and confirmatory diagnosis. Polymerase chain reaction (PCR)-based real-time detection assays may be an ideal method to detect the BTV genome in animal blood at an early stage of infection. METHODOLOGY: In this study, a SYBR green-based real-time RT-PCR assay was evaluated, validated, and compared with conventional RT-PCR. The specificity and sensitivity of an assay using BTV-2 RNA extracted from tenfold serially diluted (starting from 1.0 TCID50/mL) cell culture virus was also evaluated. RESULTS: While conventional RT-PCR could detect 3.16 × 10(2) TCID50 of virus/mL, the real-time PCR test had a detection limit of 3.16 × 10(-4) TCID50/mL. Melting curve analysis indicated the absence of non-specific amplification (R(2) = 0.987). Out of the 32 infected blood samples examined, 24 tested positive for BTV RNA. Seven that were found negative through conventional PCR tested positive through real-time PCR. CONCLUSIONS: These results showed that the SYBR green-based real-time PCR assay is rapid, sensitive, and equally specific in the diagnosis of BT in BTV-affected animals.

Human metapneumovirus: review of an important respiratory pathogen.

Human metapneumovirus (hMPV), discovered in 2001, most commonly causes upper and lower respiratory tract infections in young children, but is also a concern for elderly subjects and immune-compromised patients. hMPV is the major etiological agent responsible for about 5% to 10% of hospitalizations of children suffering from acute respiratory tract infections. hMPV infection can cause severe bronchiolitis and pneumonia in children, and its symptoms are indistinguishable from those caused by human respiratory syncytial virus. Initial infection with hMPV usually occurs during early childhood, but re-infections are common throughout life. Due to the slow growth of the virus in cell culture, molecular methods (such as reverse transcriptase PCR (RT-PCR)) are the preferred diagnostic modality for detecting hMPV. A few vaccine candidates have been shown to be effective in preventing clinical disease, but none are yet commercially available. Our understanding of hMPV has undergone major changes in recent years and in this article we will review the currently available information on the molecular biology and epidemiology of hMPV. We will also review the current therapeutic interventions and strategies being used to control hMPV infection, with an emphasis on possible approaches that could be used to develop an effective vaccine against hMPV.

Hepatitis E virus: the current scenario.

Hepatitis E infection, caused by the hepatitis E virus (HEV), is a common cause of acute hepatitis in developing countries with poor sanitation and hygiene. The virus is classified into four genotypes (1-4) with one serotype. Genotypes 1 and 2 exclusively infect humans, whereas genotypes 3 and 4 also infect other animals, particularly pigs. In endemic areas, large outbreaks of acute hepatitis caused by viruses of genotype 1 or 2 frequently occur due to fecal-oral transmission, usually through contamination of drinking water. With a high attack rate in young adults (aged 15-45 years), the disease is particularly severe among pregnant women (20-30% mortality). HEV appears to be a zoonotic disease, with transmission from pigs, wild boars, and deer, or foodborne. Chronic infections are rare, except in immunosuppressed persons, such as organ transplant recipients. A subunit vaccine has been shown to be effective in preventing the clinical disease, but is not yet commercially available. Our understanding of HEV has undergone major changes in recent years and in this article we review the currently available information with regard to the molecular biology, pathobiology, and epidemiology of HEV infection. We also review the current therapeutic interventions and strategies being used to control HEV infection, with emphasis on possible approaches that could be used to develop an effective vaccine against HEV.

Molecular detection and sequence analysis of hepatitis E virus in patients with viral hepatitis from North India.

Viral hepatitis is a major cause of mortality and morbidity in developing countries. Hepatitis E virus (HEV) is responsible for both sporadic and epidemic outbreaks of viral hepatitis in India. Here a total of 843 samples were collected: 685 from patients with acute viral hepatitis (AVH), 70 from patients with fulminant hepatic failure (FHF), 53 from patients with chronic liver disease (CLD), 11 from patients with antituberculosis therapy (ATT)-induced jaundice, and 24 from pregnant women. When tested for anti-HEV IgM, 58.3% of the pregnant women, 41.4% of the patients with FHF, 38.6% of the patients with AVH, 9.4% of the patients with CLD, and 18.2% of the patients with ATT-induced jaundice tested positive. We found that 34% and 16% of the acute hepatitis patients and fulminant hepatitis patients, respectively, showed no reactivity to the existing viral hepatitis markers and were thus grouped as non A to E. Among the HEV IgM-positive cases, males outnumbered females (62.8% versus 37.1%). HEV RNA was found in 35% of fulminant and 9.4% of acute hepatitis patients. From phylogenetic analysis, we observed that all the isolates were clustered within genotype 1. Critical analysis placed the acute isolates along with strains under subtype Ia, while the fulminant isolates clustered along with the FHF strain (X98292) under subtype Ic. The segregation of HEV isolates from AVH and FHF patients into different subtypes raises interesting questions on the molecular basis of HEV disease severity.