ABSTRACT
There is a varying prevalence of olfactory and taste dysfunction (OTD) in COVID-19 patients, with a higher prevalence reported in the European population as compared to the Asian population. Psychophysical tests are crucial to determine the exact frequency, extent and clinical characteristics of these OTDs. The present study objectively evaluated the OTD for patients treated in the Dedicated COVID-19 Hospital (DCH) in Shahdol. This prospective cross-sectional study was conducted after IEC approval in DCH Shahdol for a period of four months among RT-PCR positive patients, and they were evaluated using validated chemosensitive psychophysical test during ENT consultation to identify OTD. The sample size was calculated as 92 considering prevalence (p) of OTD as 41.3% by applying formula: n = (Z1-a/2)2 × p (1-p) / d 2. The information pertaining to the subjects was kept anonymous and confidential. During data analysis, an association was significant for p value < 0.05. It was observed that 45.5% of subjects reported either loss of taste or smell. During objective evaluation, olfactory and taste dysfunction was observed among 42.4% of subjects (95/224). The Chi-square analysis reflected statistically significant difference (p < 0.05) between subjects with OTD and without OTD for the variables such as days from onset of symptoms to admission, and symptoms (fever, sore throat and shortness of breath). Taste and smell are among the important senses and in India they are mostly subjectively evaluated for COVID-19 induced OTD which results in underreporting of these symptoms. So, a gold standard objective evaluation should be taken into consideration to evaluate OTD.
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Background: RT-PCR is the currently recommended laboratory method for diagnosing acute SARS-CoV-2 infection. Nevertheless, to carry out this assay, numerous manual steps are necessary, but they are long lasting and error-prone. A new sample preparation solution was launched, the Qiaprep & amp Viral RNA UM kit, that combines a short, liquid-based sample preparation with one-step RT-PCR amplification and detection of SARS-CoV-2. Such alternative allows reducing the handling of samples and obtaining a result in a shorter period of time. The objective of the study was to compare the performance of the kit with RT-PCR. Methods: A prospective trial was carried out in the clinical microbiology laboratory of a tertiary care hospital. The pharyngeal and nasopharyngeal swabs included in the study were taken from patients who underwent medical consultation because compatible COVID-19 symptoms. Samples were processed simultaneously for the reference RT-PCR and by the QIA P&A kit. Results: 190 samples were included in the clinical trial. The reference RT-PCR method indicated that 125 (66%) samples, out of the 190, were positive. The QIA P&A kit showed 112 positive samples for SARS-CoV-2. The QIA P&A kit has a sensitivity of 86% to detect SARS-CoV-2 and a 100% specificity, the positive predictive value was of 96%, the negative predictive value 78%, and the obtained Kappa value was 0,76. QIA P&A kit showed a lower mean cycle threshold compared with the diagnostic standard, with a statistically significant difference (p < 0.05). Conclusion: The QIA P&A kit has an acceptable, yet not optimal performance for sample preparation and amplification of SARS-CoV-2 and further studying is required for it to be validated as a cost-effective, rapid diagnostic method for detecting infections.
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Background: SARS-CoV-2 infection is associated with a wide range of clinical manifestations and severity. Pediatric cases represent <10% of total cases, with a mortality rate below 1%. Data of correlation between SARS-CoV-2 viral load in respiratory samples and severity of disease in pediatric patients is scarce. The cycle threshold (CT) value for the detection of SARS-CoV-2 could be used as an indirect indicator of viral load in analyzed respiratory samples. Objective: The aim of this study was to describe CT values and their correlation with clinical manifestations, epidemiology and laboratory parameters in pediatric patients with confirmed COVID-19. Methods: In this observational, retrospective, analytic and single-center study we included patients under 15 years with confirmed COVID-19 by RT-PCR SARS-CoV-2 admitted to the Isidoro Iriarte Hospital (Argentina) between March 1st 2020 and April 30th 2021. Results: 485 patients were included, the distribution according to disease severity was: 84% (408 patients) presented mild disease, 12% (59 patients) moderate disease and 4% (18 patients) severe disease. Patients with moderate and severe illness had an increased hospitalization rate, prolonged hospitalization, higher frequency of comorbidities and oxygen and antibiotics use. CT values, that could be used as an indirect measure of viral load, was associated with severity of clinical manifestations and age under 12 months. No patient required admission to PICU nor mechanical ventilation. No deaths were registered. Conclusions: In this study, the viral load of SARS-CoV-2 in respiratory samples, determined by the cycle threshold, was significantly correlated with moderate to severe cases and with age.
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Mutations in the genome of SARS-CoV-2 can affect the performance of molecular diagnostic assays. In some cases, such as S-gene target failure, the impact can serve as a unique indicator of a particular SARS-CoV-2 variant and provide a method for rapid detection. Here, we describe partial ORF1ab gene target failure (pOGTF) on the cobas SARS-CoV-2 assays, defined by a ≥2-thermocycle delay in detection of the ORF1ab gene compared to that of the E-gene. We demonstrate that pOGTF is 98.6% sensitive and 99.9% specific for SARS-CoV-2 lineage BA.2.12.1, an emerging variant in the United States with spike L452Q and S704L mutations that may affect transmission, infectivity, and/or immune evasion. Increasing rates of pOGTF closely mirrored rates of BA.2.12.1 sequences uploaded to public databases, and, importantly, increasing local rates of pOGTF also mirrored increasing overall test positivity. Use of pOGTF as a proxy for BA.2.12.1 provides faster tracking of the variant than whole-genome sequencing and can benefit laboratories without sequencing capabilities.
Subject(s)
COVID-19 , SARS-CoV-2 , Base Sequence , Humans , Mutation , SARS-CoV-2/geneticsABSTRACT
Introduction: We assessed the usefulness of SARS-CoV-2 RT-PCR cycle thresholds (Ct) values trends produced by the LHUB-ULB (a consolidated microbiology laboratory located in Brussels, Belgium) for monitoring the epidemic's dynamics at local and national levels and for improving forecasting models. Methods: SARS-CoV-2 RT-PCR Ct values produced from April 1, 2020, to May 15, 2021, were compared with national COVID-19 confirmed cases notifications according to their geographical and time distribution. These Ct values were evaluated against both a phase diagram predicting the number of COVID-19 patients requiring intensive care and an age-structured model estimating COVID-19 prevalence in Belgium. Results: Over 155,811 RT-PCR performed, 12,799 were positive and 7,910 Ct values were available for analysis. The 14-day median Ct values were negatively correlated with the 14-day mean daily positive tests with a lag of 17 days. In addition, the 14-day mean daily positive tests in LHUB-ULB were strongly correlated with the 14-day mean confirmed cases in the Brussels-Capital and in Belgium with coinciding start, peak, and end of the different waves of the epidemic. Ct values decreased concurrently with the forecasted phase-shifts of the diagram. Similarly, the evolution of 14-day median Ct values was negatively correlated with daily estimated prevalence for all age-classes. Conclusion: We provide preliminary evidence that trends of Ct values can help to both follow and predict the epidemic's trajectory at local and national levels, underlining that consolidated microbiology laboratories can act as epidemic sensors as they gather data that are representative of the geographical area they serve.
ABSTRACT
PURPOSE: Coronavirus disease-2019 (COVID-19) is a novel respiratory infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2); there are few specific treatments. Convalescent plasma (CP), donated by people who have recovered from COVID-19, is an investigational therapy for severe or critically ill patients with COVID-19. MATERIALS AND METHODS: This retrospective cohort study evaluated the effectiveness of CP therapy in patients with severe or life-threatening cases of COVID-19 at two hospitals in Seoul, Korea, between May and September 2020. Clinical outcomes were evaluated in 20 patients with CP therapy in a descriptive manner. Additionally, the changes in cycle threshold (Ct) values of 10 patients with CP therapy were compared to those of 10 controls who had the same (±0.8) initial Ct values but did not receive CP. RESULTS: Of the 20 patients (mean age 66.6 years), 18 received high-dose oxygen therapy using mechanical ventilators or high-flow nasal cannulas. Systemic steroids were administered to 19 patients who received CP. The neutralizing antibody titers of the administered CP were between 1:80 and 1:10240. There were two ABO-mismatched transfusions. The World Health Organization ordinal scale score and National Institutes of Health severity score improved in half of the patients within 14 days. Those who received CP showed a higher increase in Ct values at 24 h and 72 h after CP therapy compared to controls with similar initial Ct values (p=0.002). No transfusion-related side effects were observed. CONCLUSION: CP therapy may be a potential therapeutic option in severe or critically ill patients with COVID-19.