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1.
medrxiv; 2021.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2021.09.19.21262487

ABSTRACT

Studies worldwide have shown that the available vaccines are highly effective against SARS-CoV-2. However, there are growing laboratory reports that the newer variants of concerns (VOCs e.g. Alpha, Beta, Delta etc) may evade vaccine induced defense. In addition to that, there are few ground reports on health workers having breakthrough infections. In order to understand VOC driven breakthrough infection we investigated 14 individuals who tested positive for SARS-CoV-2 after being administered a single or double dose of Covishield (ChAdOx1, Serum Institute of India) from the city of Varanasi, which is located in the Indian state of Uttar Pradesh. Genomic analysis revealed that 78.6% (11/14) of the patients were infected with the B.1.617.2 (Delta) variant. Notably, the frequency (37%) of this variant in the region was significantly lower (p<0.01), suggesting that the vaccinated people were asymmetrically infected with the Delta variant. Most of the patients tested displayed mild symptoms, indicating that even a single dose of the vaccine can help in reducing the severity of the disease. However, more comprehensive epidemiological studies are required to understand the effectiveness of vaccines against the newer VOCs.


Subject(s)
Breakthrough Pain
2.
medrxiv; 2021.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2021.07.13.21260417

ABSTRACT

Emerging variants of SARS-CoV-2 with increased transmissibility or immune escape have been causing large outbreaks of COVID-19 infections across the world. As most of the vaccines currently in use have been derived from viral strains circulating in the early part of the pandemic, it becomes imperative to constantly assess the efficacy of these vaccines against emerging variants. In this hospital-based cohort study, we analysed clinical profiles and outcomes of 1161 COVID-19 hospitalized patients (vaccinated with COVISHIELD (ChAdOx1) or COVAXIN (BBV-152), n = 495 and unvaccinated n = 666) in Hyderabad, India between April 24th and May 31st 2021. Viral genome sequencing revealed that >90% of patients in both groups were harbouring the Delta variant (Pango lineage B.1.617.2) of SARS-CoV-2. Vaccinated individuals showed higher neutralizing antibodies (545+-1256 AU/ml Vs 51.1+-296 AU/ml; p<0.001) and significantly decreased Ferritin (392.26+-448.4 ng/mL Vs 544.82+-641.41 ng/mL; p<0.001) and LDH (559.45+-324.05 U/L Vs 644.99+- 294.03 U/L; p<0.001), when compared to the unvaccinated group. Severity of the disease (3.2% Vs 7.2%; p=0.0039) and requirement of ventilatory support (2.8% Vs 5.9%; p=0.0154) were significantly low in the vaccinated group despite the fact that these individuals had significantly higher age and risk factors. The rate of mortality was about 50% lower (2/132=1.51%) in the completely vaccinated breakthrough infections although mortality in individuals who had received a single dose was similar to the unvaccinated group (9/269=3.35% vs 23/666= 3.45%). Our results demonstrate that both COVISHIELD and COVAXIN are effective in preventing disease severity and mortality against the Delta variant in completely vaccinated hospitalized patients.


Subject(s)
COVID-19
3.
biorxiv; 2021.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2021.05.13.443721

ABSTRACT

Background: One of the most perplexing aspects of infection with the SARS-CoV-2 virus has been the variable response elicited in its human hosts. Investigating the transcriptional changes in individuals affected by COVID-19 can help understand and predict the degree of illness and guide clinical outcomes in diverse backgrounds. Methods: Analysis of host transcriptome variations via RNA sequencing from naso/oropharyngeal swabs of COVID-19 patients. Results: We report strong upregulation of the innate immune response, especially type I interferon pathway, upon SARS-CoV-2 infection. Upregulated genes were subjected to a comparative meta-analysis using global datasets to identify a common network of interferon stimulated and viral response genes that mediate the host response and resolution of infection. A large proportion of mis-regulated genes showed a reduction in expression level, suggesting an overall decrease in host mRNA production. Significantly downregulated genes included those encoding olfactory, taste and neuro-sensory receptors. Many pro-inflammatory markers and cytokines were also downregulated or remained unchanged in the COVID-19 patients. Finally, a large number of non-coding RNAs were identified as down-regulated, with a few of the lncRNAs associated with functional roles in directing the response to viral infection. Conclusions: SARS-CoV-2 infection results in the robust activation of the innate immunity. Reduction of gene expression is well correlated with the clinical manifestations and symptoms of COVID-19 such as the loss of smell and taste, and myocardial and neurological complications. This study provides a critical dataset of genes that will enhance our understanding of the nature and prognosis of COVID-19.


Subject(s)
COVID-19 , Cardiomyopathies , Virus Diseases
4.
biorxiv; 2020.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2020.05.31.126136

ABSTRACT

From an isolated epidemic, COVID-19 has now emerged as a global pandemic. The availability of genomes in the public domain following the epidemic provides a unique opportunity to understand the evolution and spread of the SARS-CoV-2 virus across the globe. The availability of whole genomes from multiple states in India prompted us to analyse the phylogenetic clusters of genomes in India. We performed whole-genome sequencing for 64 genomes making a total of 361 genomes from India, followed by phylogenetic clustering, substitution analysis, and dating of the different phylogenetic clusters of viral genomes. We describe a distinct phylogenetic cluster (Clade I / A3i) of SARS-CoV-2 genomes from India, which encompasses 41% of all genomes sequenced and deposited in the public domain from multiple states in India. Globally 3.5% of genomes, which till date could not be mapped to any distinct known cluster fall in this newly defined clade. The cluster is characterized by a core set of shared genetic variants - C6312A (T2016K), C13730T (A88V/A97V), C23929T, and C28311T (P13L). Further, the cluster is also characterized by a nucleotide substitution rate of 1.4 x 10-3 variants per site per year, lower than the prevalent A2a cluster, and predominantly driven by variants in the E and N genes and relative sparing of the S gene. Epidemiological assessments suggest that the common ancestor emerged in the month of February 2020 and possibly resulted in an outbreak followed by countrywide spread, as evidenced by the low divergence of the genomes from across the country. To the best of our knowledge, this is the first comprehensive study characterizing the distinct and predominant cluster of SARS-CoV-2 in India.


Subject(s)
COVID-19
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