Immune profile and responses of a novel dengue DNA vaccine encoding an EDIII-NS1 consensus design based on Indo-African sequences.

The ongoing COVID-19 pandemic highlights the need to tackle viral variants, expand the number of antigens, and assess diverse delivery systems for vaccines against emerging viruses. In the present study, a DNA vaccine candidate was generated by combining in tandem envelope protein domain III (EDIII) of dengue virus serotypes 1-4 and a dengue virus (DENV)-2 non-structural protein 1 (NS1) protein-coding region. Each domain was designed as a serotype-specific consensus coding sequence derived from different genotypes based on the whole genome sequencing of clinical isolates in India and complemented with data from Africa. This sequence was further optimized for protein expression. In silico structural analysis of the EDIII consensus sequence revealed that epitopes are structurally conserved and immunogenic. The vaccination of mice with this construct induced pan-serotype neutralizing antibodies and antigen-specific T cell responses. Assaying intracellular interferon (IFN)-γ staining, immunoglobulin IgG2(a/c)/IgG1 ratios, and immune gene profiling suggests a strong Th1-dominant immune response. Finally, the passive transfer of immune sera protected AG129 mice challenged with a virulent, non-mouse-adapted DENV-2 strain. Our findings collectively suggest an alternative strategy for dengue vaccine design by offering a novel vaccine candidate with a possible broad-spectrum protection and a successful clinical translation either as a stand alone or in a mix and match strategy.

Rapid Classification of COVID-19 Severity by ATR-FTIR Spectroscopy of Plasma Samples.

The coronavirus disease 2019 (COVID-19) pandemic continues to ravage the world, with many hospitals overwhelmed by the large number of patients presenting during major outbreaks. A rapid triage for COVID-19 patient requiring hospitalization and intensive care is urgently needed. Age and comorbidities have been associated with a higher risk of severe COVID-19 but are not sufficient to triage patients. Here, we investigated the potential of attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy as a rapid blood test for classification of COVID-19 disease severity using a cohort of 160 COVID-19 patients. A simple plasma processing and ATR-FTIR data acquisition procedure was established using 75% ethanol for viral inactivation. Next, partial least-squares-discriminant analysis (PLS-DA) models were developed and tested using data from 130 and 30 patients, respectively. Addition of the ATR-FTIR spectra to the clinical parameters (age, sex, diabetes mellitus, and hypertension) increased the area under the ROC curve (C-statistics) for both the training and test data sets, from 69.3% (95% CI 59.8-78.9%) to 85.7% (78.6-92.8%) and 77.8% (61.3-94.4%) to 85.1% (71.3-98.8%), respectively. The independent test set achieved 69.2% specificity (42.4-87.3%) and 94.1% sensitivity (73.0-99.0%). Diabetes mellitus was the strongest predictor in the model, followed by FTIR regions 1020-1090 and 1588-1592 cm-1. In summary, this study demonstrates the potential of ATR-FTIR spectroscopy as a rapid, low-cost COVID-19 severity triage tool to facilitate COVID-19 patient management during an outbreak.

HIV prevalence, risk behavior, knowledge, and beliefs among women seeking care at a sexually transmitted infection clinic in Mumbai, India.

Three hundred women presenting to a sexually transmitted infection (STI) clinic in Mumbai, India were surveyed and HIV tested. Thirty-nine percent were HIV infected; 80% were current sex workers, and HIV infection was not significantly associated with past-year sex work. Only 44% always used condoms with their noncommercial sex partners. Most believed that condom preparation is a male responsibility (58%); that condom use is a sign that partner trust is lacking (84%); and that if a woman asks her partner to use a condom, he will lose respect for her (65%). All women at STI clinics in India need HIV testing and culturally sensitive risk interventions.

SARS-CoV-2 severity classification from plasma sample using confocal Raman spectroscopy.

The world is on the brink of facing coronavirus's (COVID-19) fourth wave as the mutant forms of viruses are escaping neutralizing antibodies in spite of being vaccinated. As we have already witnessed that it has encumbered our health system, with hospitals swamped with infected patients observed during the viral outbreak. Rapid triage of patients infected with SARS-CoV-2 is required during hospitalization to prioritize and provide the best point of care. Traditional diagnostics techniques such as RT-PCR and clinical parameters such as symptoms, comorbidities, sex and age are not enough to identify the severity of patients. Here, we investigated the potential of confocal Raman microspectroscopy as a powerful tool to generate an expeditious blood-based test for the classification of COVID-19 disease severity using 65 patients plasma samples from cohorts infected with SARS-CoV-2. We designed an easy manageable blood test where we used a small volume (8 µl) of inactivated whole plasma samples from infected patients without any extra solvent usage in plasma processing. Raman spectra of plasma samples were acquired and multivariate exploratory analysis PC-LDA (principal component based linear discriminant analysis) was used to build a model, which segregated the severe from the non-severe COVID-19 group with a sensitivity of 83.87%, specificity of 70.60% and classification efficiency of 76.92%. Among the bands expressed in both the cohorts, the study led to the identification of Raman fingerprint regions corresponding to lipids (1661, 1742), proteins amide I and amide III (1555, 1247), proteins (Phe) (1006, 1034), and nucleic acids (760) to be differentially expressed in severe COVID-19 patient's samples. In summary, the current study exhibits the potential of confocal Raman to generate simple, rapid, and less expensive blood tests to triage the severity of patients infected with SARS-CoV-2.

Cytokine profile, neutralisation potential and viral replication dynamics in sera of chikungunya patients in India: a cross-sectional study.

Background: Chikungunya disease (CHIKD) is a threat to global health, as it impairs the quality of life of an infected individual ranging from months to years. A systematic evaluation of the serological, virological, and immunological aspects of the circulating viruses and their impact on the host response is imperative for better understanding of the evolving disease dynamics. Methods: Serum samples were collected from 196 acute CHIKD patients from ten tertiary care hospitals across India during 2016-2021. Out of 196 patients, paired convalescent samples were collected from 51 patients (one-month post-onset of symptoms). The serum samples were profiled for cytokines and neutralisation capacity. Further, chikungunya virus (CHIKV) was isolated from the acute sera and the replication kinetics of the clinical isolates was evaluated. Findings: Serological analysis indicated that neutralisation could be correlated to seroconversion in the convalescent phase but not found significant in acute phase. In the acute phase samples, there was a correlation between elevated serum levels of IFN-γ, IP-10, MCP-1 and MIG and disease severity. During convalescent phase, pro-inflammatory markers such as IL-6, IL-1ß, IL-9 and IP-10 were found to be elevated with a corresponding decline in the secretion of anti-inflammatory cytokines such as IL-4 and IL-10, which correlated with persistent arthralgia. Analysis of replication of the clinical isolates revealed that 68.4% of viruses were fast-growing in the Vero cells (cytopathic effect [CPE] observed within 24 h post-infection), and their corresponding acute serum samples showed an elevated secretion of IFN-α, IL-1RA, IL-17F, IL-9, MCP-1 and MIP-1α. Interpretation: This study provides an important overview of neutralisation capabilities and cytokine responses along with virus pathogenesis associated with CHIKV infections in India. Funding: Biotechnology Industry Research Assistance Council (BIRAC).

COVID-19 Serological Survey-3 Prior to Second Wave in Mumbai, India.

Background: Subsequent to serosurveys 1 and 2 for COVID-19 carried out in three wards of Mumbai in July and August 2020, Municipal Corporation of Greater Mumbai conducted serosurvey 3 in March 2021. This was to identify the extent of exposure by testing specific IgG antibodies against COVID-19. Material and Methods: A cross-sectional study was conducted to find the prevalence of seropositivity in Mumbai, which included 10,197 samples belonging to patients visiting public dispensaries (slum population, 6006) and private (nonslum population, 4191) laboratories of Aapli Chikitsa network for blood investigations for non-COVID illnesses. The ward-wise number of unlinked anonymous samples from 24 wards was predecided by using probability proportionate sampling. The samples were collected using quota sampling technique as per predecided sample for each ward. These samples collected from nonimmunized individuals were tested for IgG antibodies at the Molecular Biology Laboratory of Kasturba Hospital for Infectious Diseases by chemiluminescence assay (CLIA) method. Results: The overall seropositivity was found to be 36.3% (41.6% in slum and 28.59% in nonslum population). It was more in city wards (38.28%) followed by western suburb (36.47%) and then eastern suburb wards (34.86%), matching with the proportion of cases in these wards during the study period. There was no significant difference in seropositivity among males and females and in different age groups. Conclusions: Seropositivity is higher in slum areas than nonslum areas. It has reduced in slum areas and increased in nonslum areas as compared to findings of serosurveys 1 and 2. This explains the detection of a greater number of cases from nonslum areas in the second wave. The average seropositivity of 36.3% justifies the necessity of immunization on a wider scale in the city. Periodic serosurveys are required at fixed intervals to monitor the trend of infection and level of herd immunity.

Ocular basidiobolomycosis - Rare presentation: A case report.

Basidiobolus ranarum is an uncommon pathogen in ocular infections. It has been previously reported from subcutaneous and gastrointestinal infections. Here, we report a rare case of ocular infection caused by B. ranarum. A 21-year-old male patient presented with visual loss and pain in the right eye due to corneal abscess following an injury while welding. KOH mount performed was indicative of fungal hyphae. Fungal culture revealed growth of B. ranarum. Meanwhile, the patient was treated with antifungal (topical natamycin and oral ketoconazole) along with total corneal transplantation. B. ranarum is a fungus very uncommonly causing ocular pathogenesis. This results in diagnostic confusion leading to poor treatment outcomes. Hence, a mycology laboratory has to be aware about this fungus and need to consider it as a differential diagnosis in patients with infectious corneal abscess.

Comparison of nonstructural protein-1 antigen detection by rapid and enzyme-linked immunosorbent assay test and its correlation with polymerase chain reaction for early diagnosis of dengue.

INTRODUCTION: Early diagnosis of dengue is important for appropriate clinical management and vector control. Different serological tests based on the principle of immunochromatography and enzyme-linked immunosorbent assay (ELISA) are commonly used for detection of antigen and antibodies of dengue virus. The performance of these tests depends on the sensitivity and specificity. Hence, the study was undertaken to compare nonstructural protein-1 (NS1) antigen detection by rapid and ELISA with real-time polymerase chain reaction (RT-PCR) for diagnosis of dengue. MATERIALS AND METHODS: Prospective laboratory study was carried out on sera samples (n = 200) from clinically suspected cases of dengue. The sera samples were subjected for NS1 antigen detection test by rapid test, NS1 ELISA, and RT-PCR. The results of rapid and ELISA tests were compared with real Time PCR. RESULTS: The sensitivity, specificity, positive, and negative predictive value of rapid dengue NS1 antigen test were 81.5%, 66.7%, 78.2%, and 71.1%, respectively whereas that of NS1 ELISA were 89.9%, 100%, 100%, and 94%, respectively. Concordance of Rapid NS1 and NS1 ELISA with PCR was 75.5% and 94%. DISCUSSION AND CONCLUSION: NS1 antigen ELISA can be implemented in diagnostic laboratories for diagnosis of dengue in the acute phase of illness. The test also has great potential value for use in epidemic situations, as it could facilitate the early screening of patients and limit disease expansion.

Serum metabolomics analysis of patients with chikungunya and dengue mono/co-infections reveals distinct metabolite signatures in the three disease conditions.

Chikungunya and dengue are arboviral infections with overlapping clinical symptoms. A subset of chikungunya infection occurs also as co-infections with dengue, resulting in complications during diagnosis and patient management. The present study was undertaken to identify the global metabolome of patient sera infected with chikungunya as mono infections and with dengue as co-infections. Using nuclear magnetic resonance (NMR) spectroscopy, the metabolome of sera of three disease conditions, namely, chikungunya and dengue as mono-infections and when co-infected were ascertained and compared with healthy individuals. Further, the cohorts were analyzed on the basis of age, onset of fever and joint involvement. Here we show that many metabolites in the serum are significantly differentially regulated during chikungunya mono-infection as well as during chikungunya co-infection with dengue. We observed that glycine, serine, threonine, galactose and pyrimidine metabolisms are the most perturbed pathways in both mono and co-infection conditions. The affected pathways in our study correlate well with the clinical manifestation like fever, inflammation, energy deprivation and joint pain during the infections. These results may serve as a starting point for validations and identification of distinct biomolecules that could be exploited as biomarker candidates thereby helping in better patient management.

Chikungunya Fever Among Patients with Acute Febrile Illness Attending a Tertiary Care Hospital in Mumbai.

BACKGROUND: Chikungunya fever (CHIK) is an arboviral disease. Dengue fever (DENG) and CHIK are indistinguishable clinically and need to be differentiated by laboratory investigations. PURPOSE: This study aimed at estimating the seroprevalence of CHIK mono-infection and CHIK and DENG dual infection in suspected patients. We also analyzed the age, sex distribution, joint involvement, and relation of joint movement restriction with visual analog scale (VAS). MATERIALS AND METHODS: Two hundred patients clinically suspected with DENG and CHIK were enrolled from a Tertiary Care Hospital in Mumbai from April 2012 to October 2013. The detailed history and examination findings were recorded. Serum samples were subjected to DENG and CHIK immunoglobulin G (IgM) enzyme-linked immunosorbent assay (ELISA). RESULTS: The seroprevalence of CHIK was 12.5%. Mono-infection of CHIK was 3%, and CHIK and DENG dual infection was 9.5%. Most affected age group in CHIK cases was 46-60 years wherein female preponderance was seen. All 6 patients with CHIK mono-infection had fever and joint involvement; knee and elbow were the most commonly affected joints. All CHIK patients had VAS score of 6-10 with restricted joint movement. Of the patients with dual infection, the majorities were from 31 to 45 years with male preponderance; all had fever and joint pain mainly affecting knee and elbow. Of patients who had VAS score 6-10 in patients with dual infection, only 5.26% had restricted joint movement. CONCLUSION: IgM ELISA for Chikungunya infection should be included in the routine laboratory tests for acute febrile illness.

Development of immunochromatographic strip test using fluorescent, micellar silica nanosensors for rapid detection of B. abortus antibodies in milk samples.

Presence of bacteria such as Brucella spp. in dairy products is an immense risk to public health. Point of care immunoassays are rapid in that they can quickly screen various samples in a relatively short amount of time, are sensitive, specific and offer a great advantage in accurate and fast diagnosis of infectious diseases. We have fabricated a point of care rapid diagnostic assay that employs fluorescent, micellar silica nanosensors capable of specifically detecting Brucella IgG antibodies in milk samples of afflicted animals. Currently, point of care detection assays are not commercially available for field testing of farm animals using milk samples. The nanosensing allows precise detection of antibodies with low sample volumes (50 µl). We demonstrate recognition of B. abortus antibodies through capture by fluorescent silica nanosensors using spiked and raw milk samples validated by ELISA and PCR. The test results are accurate and repeatable with high sensitivity and specificity, and a short assay time of 10 min for antigenic recognition and do not require any sample processing procedures such as isolation and separation. Additionally, well defined antigenic components and surface biomarkers of various disease causing microbes can be broadly incorporated within the purview of this technology for accurate and rapid detection of suspected bovine pathological conditions, and can largely enable rapid field testing that can be implemented in farms and food industry.

Human immunodeficiency virus infection among tuberculosis patients in mumbai.

BACKGROUND: Human Immunodeficiency Virus (HIV) is the most powerful risk factor for the progression of Mycobacterium tuberculosis infection to Tuberculosis (TB) disease. TB accelerates the progression of HIV infection to AIDS and shortens the survival of such patients. AIM: To determine the seroprevalence of HIV infection among TB confirmed patients in a tertiary care center in Mumbai in view of the significance of HIV in TB. Its association with gender and age was also determined. MATERIALS AND METHODS: Blood samples were collected by venipuncture from 432 TB patients and their HIV status was determined. HIV antibody detection was carried out as per Strategy III, National AIDS Control Organisation (NACO) guidelines. Statistical analysis was carried out by applying the Chi-square test. RESULTS AND CONCLUSION: Of the 432 patients screened, 9% (39) were HIV positive. The prevalence of co-infection was higher among females (9.4%) than the male (8.7%) patients and highest amongst those aged 21to40 years (13.7%). Co-infection was found to be statistically highly associated with age (p < 0.05). This high prevalence calls for routine screening of TB patients for HIV infection.