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1.
Viruses ; 14(10)2022 10 12.
Article in English | MEDLINE | ID: covidwho-2071834

ABSTRACT

In SARS-CoV-2 diagnostics, cycle threshold (Ct) values from qRT-PCRs semi-quantitatively estimate a patient's viral load. However, relevant analytical differences between qRT-PCR assays are often neglected. This study was designed (i) to identify such differences between five commonly used assays and (ii) to demonstrate a straightforward strategy to harmonize them. QRT-PCRs for SARS-CoV-2 were carried out in 85 oropharyngeal swab samples using three fully automated (Alinity m, cobas®6800 and GeneXpert) and two semi-automated (genesig® and RIDA®GENE) assays. Qualitative results (positive/negative) showed excellent comparability between the fully automated assays, but not between the Alinity m and semi-automated methods. Ct values significantly varied between all the methods, with the median values ranging from 22.76 (Alinity m) to 30.89 (RIDA®GENE) and 31.50 (genesig®), indicating the lowest sensitivity for semi-automated methods. Passing-Bablok analysis further revealed systemic biases. Assay-specific viral load concentration calculations-based on generated individual standard curves-resulted in much better comparability between the assays. Applying these calculations, significant differences were no longer detectable. This study highlights relevant analytical differences between SARS-CoV-2 qRT-PCR assays, leading to divergent decisions about the mandatory isolation of infected individuals. Secondly, we propose a strategy to harmonize qRT-PCR assays to achieve better comparability. Our findings are of particular interest for laboratories utilizing different assays.


Subject(s)
COVID-19 , Scrapie , Sheep , Animals , Humans , SARS-CoV-2/genetics , COVID-19 Testing , COVID-19/diagnosis , Reverse Transcriptase Polymerase Chain Reaction , Sensitivity and Specificity
2.
Haseki Tip Bulteni ; 60(4):318-324, 2022.
Article in English | EMBASE | ID: covidwho-2066931

ABSTRACT

Aim: We think that the nasopharyngeal swab sample should be taken bilaterally to improve the sensitivity of the real-time-reverse transcriptase-polymerase chain reaction (RT-PCR) test since there may be pathologies that cause nasal obstruction, such as nasal septum deviation (NSD). In this context, we investigated the effect of the nasopharyngeal swab sampling method and the presence of nasal obstruction on the detection of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2). Method(s): This prospective clinical study was conducted from March 2021 to January 2022. Forty-four hospitalized patients with NSD were included in the study group, and 44 hospitalized patients without NSD were included in the control group. The results of the RT-PCR test studied with a unilateral nasopharyngeal swab sample taken during hospitalization and the RT-PCR test studied with a bilateral nasopharyngeal swab sample taken on the 2nd day of hospitalization and the visual analog scale (VAS) scores showing the patients' pain during the first sampling were determined. Result(s): In the first test, 23 (52.3%) patients in the study group and 32 (72.7%) patients in the control group were evaluated as SARS-CoV-2 positive. The first test sensitivity was significantly higher in the control group (p=0.048). The VAS score was significantly higher in the study group (p=0.00008). In the second test, 35 (79.5%) patients in the study group and 37 (84.1%) patients in the control group were evaluated as SARS-CoV-2 positive. The sensitivity increases in the study group and in the population were statistically significant (p=0.007 and p=0.004, respectively). The consistency of the first and second test results increased in patients without NSD and in patients with low VAS scores [odds ratio (OR)=3.779;p=0.001, OR=2.572;p=0.005, respectively]. Conclusion(s): Nasopharyngeal swab sampling may be affected by nasal congestion and the sampling method. To avoid this, it may be more appropriate to take a nasopharyngeal swab sample through the bilateral nasal cavity. Copyright © 2022 by The Medical Bulletin of Istanbul Haseki Training and Research Hospital The Medical Bulletin of Haseki published by Galenos Yayinevi.

3.
Asian Journal of Medical Sciences ; 13(10):168-171, 2022.
Article in English | Academic Search Complete | ID: covidwho-2065389

ABSTRACT

Background: COVID-19 pandemic continues to be a public health threat. Rapid antigen tests (RATs) for the detection of SARS-CoV-2 infection will help in formulation of clinical and public health strategies for the control of transmission. In India, 49% of COVID-19 tests done are RATs.¹ The sensitivity of RAT is 50.6–84%. RAT has specificity ranging from 99.3% to 100%.² The present study aims at evaluating the RAT screening test done on people attending fever clinic of Shimoga Institute of Medical Sciences, Shivamogga. Aims and Objectives: The objectives of the study were to evaluate the COVID-19 RAT screening test with reverse transcriptase-polymerase chain reaction (RT-PCR) as the gold standard test done at fever clinic of SIMS, Shimoga. Materials and Methods: An observational, cross-sectional analytical study was conducted for a period of 1 month, May 2021. The study participants included all the people attending fever clinic of SIMS, Shimoga. Assuming the sensitivity of RAT to be 85%, power of 80%, and precision of 5%, the calculated sample size was 204. Considering non-response rate of 10%, the final sample size was 224. Secondary data regarding contact number of the people attending fever clinic were collected from the COVID-19 test register. Oral consent was taken after explaining about study and assuring confidentiality. Telephonic interview was done to collect relevant information. Analysis was done using Epi Info software version 7.2.4.0. Descriptive statistics such as percentages and analytical statistics such as Student’s t-test and Chi-square test were used. Results: Overall positivity rate was 43.7%. About 71% of people had contact history. Sensitivity and specificity of RAT test were found to be 64.2% and 97.2%, respectively, and were comparable with the previous studies. Significant difference was found (P<0.05) between RAT and RT-PCR results. Conclusion: Significant difference was found between RAT and RT-PCR results which indicate that RAT is not diagnostic for people who test positive in RT-PCR. Sensitivity of RAT is relatively less in our study (but crucial in detecting disease early) and hence we strongly recommend that RT-PCR for those who test negative for RAT test. [ FROM AUTHOR] Copyright of Asian Journal of Medical Sciences is the property of Manipal Colleges of Medical Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

4.
AJN American Journal of Nursing ; 122(10):15-15, 2022.
Article in English | Academic Search Complete | ID: covidwho-2062991

ABSTRACT

The article announces the appointment of Ann Kurth as the next president of the New York Academy of Medicine (NYAM), the first nurse and first nonphysician to lead the institution.

5.
Eur J Radiol Open ; 9: 100438, 2022.
Article in English | MEDLINE | ID: covidwho-2061087

ABSTRACT

Objectives: When diagnosing Coronavirus disease 2019(COVID-19), radiologists cannot make an accurate judgments because the image characteristics of COVID-19 and other pneumonia are similar. As machine learning advances, artificial intelligence(AI) models show promise in diagnosing COVID-19 and other pneumonias. We performed a systematic review and meta-analysis to assess the diagnostic accuracy and methodological quality of the models. Methods: We searched PubMed, Cochrane Library, Web of Science, and Embase, preprints from medRxiv and bioRxiv to locate studies published before December 2021, with no language restrictions. And a quality assessment (QUADAS-2), Radiomics Quality Score (RQS) tools and CLAIM checklist were used to assess the quality of each study. We used random-effects models to calculate pooled sensitivity and specificity, I2 values to assess heterogeneity, and Deeks' test to assess publication bias. Results: We screened 32 studies from the 2001 retrieved articles for inclusion in the meta-analysis. We included 6737 participants in the test or validation group. The meta-analysis revealed that AI models based on chest imaging distinguishes COVID-19 from other pneumonias: pooled area under the curve (AUC) 0.96 (95 % CI, 0.94-0.98), sensitivity 0.92 (95 % CI, 0.88-0.94), pooled specificity 0.91 (95 % CI, 0.87-0.93). The average RQS score of 13 studies using radiomics was 7.8, accounting for 22 % of the total score. The 19 studies using deep learning methods had an average CLAIM score of 20, slightly less than half (48.24 %) the ideal score of 42.00. Conclusions: The AI model for chest imaging could well diagnose COVID-19 and other pneumonias. However, it has not been implemented as a clinical decision-making tool. Future researchers should pay more attention to the quality of research methodology and further improve the generalizability of the developed predictive models.

6.
Indian J Public Health ; 66(3): 276-281, 2022.
Article in English | MEDLINE | ID: covidwho-2055735

ABSTRACT

Background: Real-time reverse transcriptase-polymerase chain reaction (RT-PCR) kits have been reliably employed for the diagnosis of coronavirus disease 2019 (COVID-19) by the detection of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA since the beginning of the disease outbreak. In consideration of reliable diagnosis, apart from RT-PCR, the isothermal nucleic acid amplification-based point-of-care automated kits have also been tagged as a simpler and rapid alternative to the conventional techniques. Currently, the availability of a better diagnostic method for COVID-19 when compared to RT-PCR is nil. The most important step in the detection of SARS-CoV-2 in a RT-PCR diagnostic laboratory is to identify and employ RT-PCR kits with higher sensitivity as well as specificity. Objectives: This study aimed to study commercially available RT-PCR kits for the detection of SARS-CoV-2 infections. Methods: The performance of seven different RT-PCR kits from different manufacturers used for diagnosis of COVID-19 in Govt Theni Medical College and Hospital, Theni, Tamil Nadu were analysed. Nasopharyngeal and oropharyngeal swabs were collected from patients and subjected to RT-PCR using these kits. Results and Conclusion: The sensitivities and batch effects of the assessed kits were slightly different for different targets, for SARS-CoV-2 detection in nasopharyngeal swab specimens. Examination of COVID-19 kits should be done using currently employed kits in routine diagnosis for better efficiency.


Subject(s)
COVID-19 , Nucleic Acids , COVID-19/diagnosis , COVID-19 Testing , Clinical Laboratory Techniques/methods , Humans , India/epidemiology , RNA , RNA-Directed DNA Polymerase , Reverse Transcriptase Polymerase Chain Reaction , SARS-CoV-2/genetics , Sensitivity and Specificity
7.
J Obstet Gynaecol India ; : 1-7, 2022 Sep 22.
Article in English | MEDLINE | ID: covidwho-2041337

ABSTRACT

Background: Whether vertical transmission or placental pathology occurs after maternal infection during pregnancy remains unknown. There is a clear need for studies on the impact of COVID-19 on pregnancy outcome. A systemic inflammatory or hypercoagulable state may be the contributing factor for placental pathology. Methods: The pregnant women with COVID-19 who delivered between May 2020 and May 2021 were followed and data were collected about pregnancy course and placentas were examined for macro- and microscopical changes and were compared to controls with non-infected women. Results: Placenta of COVID-19-infected females had increased prevalence of decidual arteriopathy and placental injury reflecting hypoxia and uteroplacental insufficiency within the intervillous space. Features of maternal vascular malperfusion such as increased syncytial knots were present in 100% cases. Fibrinoid necrosis was seen in 100% cases and increased focal perivillous fibrin depositions were presented in 37.7% cases. About one fourth infected placentas had evidence of villitis. Even after matching for comorbidities like preeclampsia, these changes were present. Conclusion: The most common pathological findings of the placenta of COVID-19 infections are signs of maternal and fetal malperfusion. Future studies should target infections in different stage of gestation, including first and second trimesters.

8.
Jordan Journal of Biological Sciences ; 15(3):395-404, 2022.
Article in English | GIM | ID: covidwho-2040762

ABSTRACT

Chest radiographic (CXR) and chest computed tomography (CT) scans have been used to diagnose coronavirus (COVID-19) disease as an important counterpart to the reverse transcription polymerase chain reaction (RT-PCR) diagnostic protocol. This work explores the application of CXR and CT scans as diagnostic instruments for COVID-19. Numerous databases were searched from 01/01/2020 till 2020 late for COVID-19 articles which documented the clinical features of CXR and CT scans. The documented cases were based on the evaluation of the imaging characteristics. Chest radiographic findings may be confirmed with the most basic CT scans. Peripheral, bilateral and primary ground-glass distortion are the most prominent CT results with COVID-19 infections. In conclusion, unique and ambiguous terms such as pneumonia, blurred opacities, airspace disease, patchy opacities, and infiltrates make it difficult to perceive the different chest radiographic findings.

9.
Chinese Veterinary Science / Zhongguo Shouyi Kexue ; 50(12):1500-1508, 2020.
Article in Chinese | CAB Abstracts | ID: covidwho-2040500

ABSTRACT

Based on the M gene sequence of TGEV and PEDV and VP2 gene sequence of PoRV, the optimal reaction system and amplification procedure were established by optimizing primer, probe concentration and annealing temperature, and the Quantitative PCR method of TaqMan probes for three viruses is successfully established. On this basis, after further optimization of conditions, a triple real-time fluorescent quantitative PCR method for detecting TGEV, PEDV, and PoRV was established. The detection sensitivity of this method for TGEV, PEDV, and PoRV were 2.49 copies/ L, 4.36 copies/ L, and 4.96 copies/ L respectively. The maximum value of CV in repeated trials detected by TGEV, PEDV and PoRV were 2.5%, 3.8%, 4.3%, and the maximum value of CV in repeated trials between groups were 3.7%, 3.4%, 3.2%, which are no more than 5%.indicating that the established method has good reproducibility. Using this method to detect PRV, PCV1, and PRRSV virus samples, there is no cross-reaction, indicating that the method is specific. Using the established method to detect 40 clinical diseases, the samples were tested, and the positive rates of TGEV, PEDV, and PoRV were 5%, 30%, and 12.5%respectively. The mixed infection rate of TGEV and PEDV was 2.5%, the mixed infection rate of PEDV and PoRV was 5%. The results of the multiple fluorescence quantitative PCR method are consistent with those of the detection of a single fluorescent RT-PCR method, indicating that the established method has good clinical application value.

10.
Chinese Journal of Virology ; 36(6):1171-1176, 2020.
Article in Chinese | GIM | ID: covidwho-2040435

ABSTRACT

Coronavirus disease 2019 (COVID-19) is caused by infection by SARS-COV-2.. The main clinical manifestations are fever, cough, fatigue, respiratory distress, and even death. The virus is highly contagious, spreads mainly through droplets, and has wrought havoc upon human health, national economies, and public-health systems worldwide. The clinical diagnosis is based mainly on clinical manifestations, computed tomography of the chest, and laboratory examinations. For the latter, real-time fluorescent reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and genome sequencing are the "gold standard" for the diagnosis. Choosing a rapid and efficient method for pathogen detection has a key role in improving the diagnosis rate, cure rate, as well as reducing morbidity and mortality. Compared with genome sequencing, RT-qPCR has the advantages of simple operation and short cycle, which is particularly important for the diagnosis of SARS-CoV-2. Here, we review the sensitivity, specificity, and practicality of different methods of RT-qPCR for detection of the nucleic acids of SARS-CoV-2, and provide a reference for clinicians to choose more efficient detection methods for nucleic acids.

11.
Journal of Datta Meghe Institute of Medical Sciences University ; 17(5):S128-S134, 2022.
Article in English | Scopus | ID: covidwho-2040155

ABSTRACT

COVID-19 is a sickness brought about by coronavirus responsible for causing simple to extreme complications in people. COVID-19 first case was seen in Wuhan, Hubei Province, China, on December, 2019. The World Health Organization (WHO) to pronounce it as a worldwide pandemic on March 11, 2020, as the pandemic has spread quickly all through the world. Regardless of extensive endeavors made to contain the infection, the infection has proceeded with its pervasiveness in numerous nations with changing levels of clinical signs. Henceforth, in this report, we discuss the various strategies, for example, serological and nucleic acid-based procedures which are accessible for the determination and successful counteraction of coronavirus. With expanding the rate of coronavirus cases, the precise and early identification of the COVID-19 is the need of great importance for viable avoidance with treatment and just as to check its spread. Reverse transcriptase-real time polymerase chain reaction (PCR) measures are viewed as the highest quality level for the early identification of infection. This diagnostic technique is being utilized worldwide with recommendations from WHO and Center for Disease Control and Prevention. Reverse transcriptase real-time quantitative PCR (RT-qPCR) is being done compulsory before any medical procedures and major surgeries for early detection, prevention, and management in due time course. Rapid antigen test is also a screening test used widely in hospitals for screening of COVID-19 and before the admission in hospitals. Other nucleic acid amplification test widely done for the detection of COVID-19 are RT-qPCR, next-generation sequencing, clustered regularly interspaced short pallindromic repeats, reverse transcription -loop-mediated isothermal amplification, droplet digital PCR. Some immunological tests are lateral flow, ELISA. © 2022 Wolters Kluwer Medknow Publications. All rights reserved.

12.
Sri Lankan Journal of Infectious Diseases ; 12(2), 2022.
Article in English | CAB Abstracts | ID: covidwho-2040070

ABSTRACT

Real time RT-PCR is considered as the gold standard test to detect COVID-19. The use of sample pooling strategy increases testing capacity and spares resources. However, the effectiveness of sample pooling should be evaluated in the setting before being implemented. Forty five samples including 20 high positives (Ct<20), 20 low positives (Ct 20-40) and 05 negative samples were used to prepare 1:1, 1:3 and 1:5 simulated sample pools which were then subjected to viral RNA extraction followed by real time RT-PCR. Sensitivity and specificity of sample pooling technique in the detection of SARS-CoV-2 RNA was 100% without significant variation of Ct values. According to our results, pooling of up to 6 samples will not have an effect on the final result in clinical samples and hence can be adopted in the given context for the diagnosis of COVID-19 by RT-PCR.

13.
PLoS Global Public Health ; 2(8), 2022.
Article in English | CAB Abstracts | ID: covidwho-2039238

ABSTRACT

Between March 2020 and February 2021, the state of Baja California, Mexico, which borders the United States, registered 46,118 confirmed cases of COVID-19 with a mortality rate of 238.2 deaths per 100,000 residents. Given limited access to testing, the population prevalence of SARS-CoV-2 infection is unknown. The objective of this study is to estimate the seroprevalence and real time polymerase chain reaction (RT-PCR) prevalence of SARS-CoV-2 infection in the three most populous cities of Baja California prior to scale-up of a national COVID-19 vaccination campaign. Probabilistic three-stage clustered sampling was used to conduct a population-based household survey of residents five years and older in the three cities. RT-PCR testing was performed on nasopharyngeal swabs and SARS-CoV-2 seropositivity was determined by IgG antibody testing using fingerstick blood samples. An interviewer-administered questionnaire assessed participants' knowledge, attitudes, and preventive practices regarding COVID-19. In total, 1,126 individuals (unweighted sample) were surveyed across the three cities. Overall prevalence of SARS-CoV-2 infection by RT-PCR was 7.8% (95% CI 5.5-11.0) and IgG seroprevalence was 21.1% (95% CI 17.4-25.2). There was no association between border crossing in the past 6 months and SARS-CoV-2 prevalence (unadjusted OR 0.40, 95%CI 0.12-1.30). While face mask use and frequent hand washing were common among participants, quarantine or social isolation at home to prevent infection was not. Regarding vaccination willingness, 30.4% (95% CI 24.4-3 7.1) of participants said they were very unlikely to get vaccinated. Given the high prevalence of active SARS-CoV-2 infection in Baja California at the end of the first year of the pandemic, combined with its low seroprevalence and the considerable proportion of vaccine hesitancy, this important area along the Mexico-United States border faces major challenges in terms of health literacy and vaccine uptake, which need to be further explored, along with its implications for border restrictions in future epidemics.

14.
Lung India ; 39(5):422-427, 2022.
Article in English | Academic Search Complete | ID: covidwho-2030166

ABSTRACT

Background: Coronavirus disease 2019 (COVID-19) can cause asymptomatic, mild upper respiratory tract symptoms and pneumonia in young persons. How the disease will progress in each patient is still unknown. Therefore, we aimed to investigate the prognostic markers of the development of pneumonia and the clinical characteristics of patients under 65 years with COVID-19 confirmed by a positive reverse transcriptase polymerase chain reaction test. Methods: In this retrospective study, a total of 271 patients admitted in our unit were included. The patients were divided into two groups, those who did and those who did not develop pneumonia. Their clinical features, treatment protocols, and laboratory parameters were recorded retrospectively. Results: Pneumonia developed in 67.9% (n = 184) of the cases. The age in the pneumonia group was higher than that in the non-pneumonia group (p < 0.001). In the logistic regression analysis, the symptom and co-morbidity status were examined according to the presence of pneumonia;hypertension (HT) (OR: 4525, 95% CL: 1,494-13,708) was the most important risk factor for pneumonia. When age and laboratory values were examined according to the presence of pneumonia, advanced age (OR: 1.042, 95% CL: 1.01-1.073), low albumin (OR: 0.917, 95% CL: 0.854-0.986), and high troponin (OR: 1.291, 95% CL: 1.044-1.596) were identified as risk factors for pneumonia. Conclusion: In this article, HT (22.3%, P < 0.001) has been considered as an important risk factor, whereas association of diabetes mellitus (21.2%, P 0.029) and smoking (25.0%, P 0.038) was also significant. The median age of the group was 51 (41.5-58) in the group developing pneumonia and 41 (30-48) in the non-developing group. Young patients with these predictive factors should be more carefully evaluated by further diagnostic procedures, such as thoracic computed tomography. [ FROM AUTHOR] Copyright of Lung India is the property of Wolters Kluwer India Pvt Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

15.
Osmaniye Korkut Ata Universitesi Fen Bilimleri Enstitusu Dergisi / Osmaniye Korkut Ata University Journal of Natural and Applied Sciences ; 5(2):505-521, 2022.
Article in English | GIM | ID: covidwho-2026790

ABSTRACT

The infection called Covid-19 caused by the new type of coronavirus (SARS-CoV-2) is an epidemic and deadly disease that spreads rapidly worldwide. Early detection of Covid-19 will enable the patient to receive appropriate treatment and increase the chance of survival. This study aims to investigate the detection of poor prognosis from chest CT images in Covid-19 patients who died and healed using deep learning. In this retrospective study which was carried out in collaboration with a specialist radiologist, a dataset was created by evaluating a total of 5997 CT images by the expert. Images belonging to two classes in the dataset were classified using the Inception-v3 deep learning model. In order to evaluate the classifier, ROC curves were drawn, AUC and accuracy values were used as performance metrics. Inception-v3 model was run 10 times, and a maximum classification performance of 97.55% and an average of 97.01% was achieved. The classification results prove that Inception-v3 can classify CT images with a high accuracy rate for evaluating the Covid-19 prognosis.

16.
Journal of Pure & Applied Microbiology ; 16(3):2110-2116, 2022.
Article in English | Academic Search Complete | ID: covidwho-2026231

ABSTRACT

Like elsewhere around the globe, SARS-CoV-2 infection is spreading in rural Egypt. Due to high sensitivity and specificity, the gold standard of diagnostics is reverse transcription polymerase chain reaction PCR (RT-PCR). Rural areas without access to certified laboratories cannot take advantage of RT-PCR testing, and thus are dependent upon rapid antigen testing, a point-of-care test that requires less training and can produce results within 15 minutes. Rapid antigen testing can give an advantage to medical teams in rural settings by affording effective and early control of SARS-CoV-2 infection spread. We sought to assess the contribution of different COVID-19 testing procedures in rural Egypt. We conducted a prospective cohort study in a rural lab in Giza, Egypt. Approximately 223 individuals with potential SARS-CoV-2 infection were involved in the study during the pandemic peak in Giza, Egypt, from March 4 - May 30, 2021. Subjects were subjected to RT-PCR and rapid antigen testing, and the performance of each testing procedure was compared. Between March 4 - May 30, 2021, approximately 223 symptomatic individuals were included in this study. 190 patients (85.2%) were indicated as PCR positive for SARSCoV-2, while 33 (14.8%) were PCR negative. In comparison, a rapid antigen test showed 178 out of 223 patients (79.8%) were indicated as positive, or 94% of the PCR-positive individuals. In Giza, a rural area of Egypt, RT-PCR had an optimal balance of sensitivity and specificity, however, the turnaround time was a limiting factor. Antigen testing, performed as a rapid point-of-care test, can play an effective role in rural outbreak control due to its ease of use and rapid results. [ FROM AUTHOR] Copyright of Journal of Pure & Applied Microbiology is the property of Dr. M. N. Khan and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

17.
Wiener Tierarztliche Monatsschrift ; 109(Artikel 11), 2022.
Article in English | CAB Abstracts | ID: covidwho-2025202

ABSTRACT

We have evaluated the diagnostic performance of immunochromatographic point-of-care tests (POCT) for the detection of rotavirus, coronavirus, Escherichia (E.) coli F5, Cryptosporidium (C.) parvum, Clostridium (Cl.) perfringens and Giardia (G.) intestinalis in fresh and thawed faecal samples from calves aged up to six months with diarrhoea. We performed POCTs to detect rotavirus, coronavirus, E. coli F5, C. parvum, Cl. perfringens and G. intestinalis on fresh samples in a field study and re-evaluated the performance for C. parvum, Cl. perfringens and G. intestinalis using thawed samples. We calculated the performance based on the results of the reference methods, which were RT-qPCR for the detection of rota- and coronavirus and bacteriological culturing and PCR to detect E. coli F5 and Cl. perfringens a and ss2 toxins. C. parvum was detected by phase-contrast microscopy and G. intestinalis by immunofluorescence microscopy. We collected 177 faecal samples from diarrhoeic calves. We found good performance for the POCT targeting rotavirus (sensitivity (SE)=92.9%;specificity (SP)=95.6%) and C. parvum (SE=63.3%;SP=96.2%). For E. coli F5, the number of true positive samples (n=1) was too low to evaluate the performance. The POCT to detect coronavirus gave a poor performance (SE=3.3%;SP=96.6%) and the POCT to detect Cl. perfringens a moderate performance (SE=52.8%;SP=78.2%). G. intestinalis POCT showed a higher sensitivity to immunofluorescence microscopy in thawed than in fresh faecal samples (SE=43.9% versus SE=29.2%). There are substantial differences in diagnostic performance between the commercially available immunochromatographic POCTs. Still, POCT can make a valuable contribution to the diagnosis and prevention of calf diarrhoea.

18.
PLoS Global Public Health ; 2(6), 2022.
Article in English | CAB Abstracts | ID: covidwho-2021474

ABSTRACT

COVID-19 mortality rate has not been formally assessed in Nigeria. Thus, we aimed to address this gap and identify associated mortality risk factors during the first and second waves in Nigeria. This was a retrospective analysis of national surveillance data from all 37 States in Nigeria between February 27, 2020, and April 3, 2021. The outcome variable was mortality amongst persons who tested positive for SARS-CoV-2 by Reverse-Transcriptase Polymerase Chain Reaction. Incidence rates of COVID-19 mortality was calculated by dividing the number of deaths by total person-time (in days) contributed by the entire study population and presented per 100,000 person-days with 95% Confidence Intervals (95% CI). Adjusted negative binomial regression was used to identify factors associated with COVID-19 mortality. Findings are presented as adjusted Incidence Rate Ratios (aIRR) with 95% CI. The first wave included 65,790 COVID-19 patients, of whom 994 (1.51%) died;the second wave included 91,089 patients, of whom 513 (0.56%) died. The incidence rate of COVID-19 mortality was higher in the first wave [54.25 (95% CI: 50.98-57.73)] than in the second wave [19.19 (17.60-20.93)]. Factors independently associated with increased risk of COVID-19 mortality in both waves were: age =45 years, male gender [first wave aIRR 1.65 (1.35-2.02) and second wave 1.52 (1.11-2.06)], being symptomatic [aIRR 3.17 (2.59-3.89) and 3.04 (2.20-4.21)], and being hospitalised [aIRR 4.19 (3.26-5.39) and 7.84 (4.90-12.54)]. Relative to South-West, residency in the South-South and North-West was associated with an increased risk of COVID-19 mortality in both waves. In conclusion, the rate of COVID-19 mortality in Nigeria was higher in the first wave than in the second wave, suggesting an improvement in public health response and clinical care in the second wave. However, this needs to be interpreted with caution given the inherent limitations of the country's surveillance system during the study.

19.
Int J Infect Dis ; 123: 58-69, 2022 Oct.
Article in English | MEDLINE | ID: covidwho-2015423

ABSTRACT

OBJECTIVES: The aim of this study was to evaluate the time in days between symptom onset and first positive real-time reverse transcriptase polymerase chain reaction (RT-PCR) result for COVID-19. METHODS: This systematic review was conducted in the MEDLINE (PubMed), Embase, and Scopus databases using the following descriptors: "COVID-19", "SARS-CoV-2", "coronavirus", "RT-PCR", "real time PCR", and "diagnosis". RESULTS: The included studies were conducted in 31 different countries and reported on a total of 6831 patients. The median age of the participants was 49.95 years. The three most common symptoms were fever, cough, and dyspnea, which affected 4012 (58.68%), 3192 (46.69%), and 2009 patients (29.38%), respectively. Among the 90 included studies, 13 were prospective cohorts, 15 were retrospective cohorts, 36 were case reports, 20 were case series, and six were cross-sectional studies. The overall mean time between symptom onset and positive test result was 6.72 days. Fourteen articles were analyzed separately for the temporal profile of RT-PCR test results; the best performance was on days 22-24, when 98% of test results were positive. CONCLUSION: These findings corroborate the RT-PCR COVID-19 testing practices of some health units. In addition, the most frequently described symptoms of these patients can be considered the initial symptoms of infection and used in decision-making about RT-PCR testing.


Subject(s)
COVID-19 , COVID-19/diagnosis , COVID-19 Testing , Clinical Laboratory Techniques/methods , Humans , Middle Aged , Prospective Studies , RNA-Directed DNA Polymerase , Real-Time Polymerase Chain Reaction , Retrospective Studies , Reverse Transcriptase Polymerase Chain Reaction
20.
Urmia Medical Journal ; 32(10):782-792, 2022.
Article in English | GIM | ID: covidwho-2012533

ABSTRACT

Background & Aims: Favipiravir is an antiviral drug that is widely used in patients with Covid-19. The aim of this study was to review the systematic review and meta-analysis studies of Favipiravir in patients with Covid-19. Materials & Methods: An electronic search was conducted in PubMed, Scopus, Cochrane Library, and Web of Science databases until December 2021. In addition, other databases were searched. A manual search of studies and other sources was also conducted to find evidence. The Overview Quality Assessment Questionnaire tool was used to evaluate the quality of articles.

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