Radiological findings spectrum of asymptomatic coronavirus (COVID-19) patients

BackgroundRadiological examinations of COVID-19 positive patients play a vital role in early diagnosis and assessment of disease course, as most COVID-19 infected patients were diagnosed with pneumonia and characteristic CT imaging patterns. Asymptomatic infected individuals, called "asymptomatic carrier or transmitter”, who are the infectious sources of SARS-CoV-2, and some of them progress rapidly, even resulting in acute respiratory distress syndrome (ARDS) with a high case-fatality rate. Our study is a prospective study and aims to be familiar with the CT imaging features of asymptomatic cases with COVID-19 pneumonia.ResultsA total of 44 asymptomatic cases with COVID-19 pneumonia between March 20, 2020 and May 23, 2020 were enrolled. All patients had a history of exposure to SARS-CoV-2 or recent travel history. All patients had no symptoms. The predominant feature of CT findings in this cross-sectional study was ground-glass opacity (GGO) (41, 93%) with peripheral (34, 77.3%) distribution, bilateral location (20, 45.5%) with lower lobe predominance (left lower lobe 72% and right lower lobe 50%).ConclusionCT imaging of asymptomatic cases with COVID-19 pneumonia has highly characteristics findings. Since asymptomatic patients are the asymptomatic transmitter, and some patients can progress rapidly in the short term, it is essential to early diagnose asymptomatic patients with COVID-19. CT scan has great sensitivity in screening and detecting patients with COVID-19 pneumonia.

A Counterintuitive Neutrophil-Mediated Pattern in COVID-19 Patients Revealed through Transcriptomics Analysis.

The COVID-19 pandemic has persisted for almost three years. However, the mechanisms linked to the SARS-CoV-2 effect on tissues and disease severity have not been fully elucidated. Since the onset of the pandemic, a plethora of high-throughput data related to the host transcriptional response to SARS-CoV-2 infections has been generated. To this end, the aim of this study was to assess the effect of SARS-CoV-2 infections on circulating and organ tissue immune responses. We profited from the publicly accessible gene expression data of the blood and soft tissues by employing an integrated computational methodology, including bioinformatics, machine learning, and natural language processing in the relevant transcriptomics data. COVID-19 pathophysiology and severity have mainly been associated with macrophage-elicited responses and a characteristic "cytokine storm". Our counterintuitive findings suggested that the COVID-19 pathogenesis could also be mediated through neutrophil abundance and an exacerbated suppression of the immune system, leading eventually to uncontrolled viral dissemination and host cytotoxicity. The findings of this study elucidated new physiological functions of neutrophils, as well as tentative pathways to be explored in asymptomatic-, ethnicity- and locality-, or staging-associated studies.

COVID-19 screening in asymptomatic patients scheduled for surgery. What is the role of rt-PCR in elective procedures during the pandemic?

Background: COVID-19 has changed medical practice nowadays. One of the biggest concerns has been establishing when invasive procedures such as surgery, GI endoscopy or bone marrow transplant are safe;and if it is necessary to consider screening for asymptomatic patients. Method(s): We identified asymptomatic patients that were scheduled for invasive procedures from May 2020 to April 2021 at Clinica de Marly. Patients were asked to fill a questionnaire about GI and upper respiratory symptoms and contact with possible/confirmed cases of COVID- 19 in the last 15 days. Patients taken to emergency procedures, who had symptoms or contact with probable/confirmed cases in the last 15 days were excluded. rt-PCR was performed to screen COVID-19. Result(s): A total of 1837 patients were included. 104 rt-PCRs tested positive for SARS-CoV-2, leading to a 5.66% of identified asymptomatic patients. Patients were followed-up on the 30th day after the procedure. 1733 negative patients responded to our follow-up, in which only 1 death and 2 complications were detected. 102 positive patients were followed-up and no complications or deaths were reported. Conclusion(s): We found the presence of 5.66% of asymptomatic patients with positive rt-PCR for COVID-19. Safe screening will decide if these invasive interventions can be postponed, or, if the benefit outweighs the risks.Copyright © 2022 Asociacion Colombiana de Infectologia. All rights reserved.

Optimization of sewage sampling for wastewater-based epidemiology through stochastic modeling

The proliferation of the SARS-CoV-2 global pandemic has brought to attention the need for epidemiological tools that can detect diseases in specific geographical areas through non-contact means. Such methods may protect those potentially infected by facilitating early quarantine policies to prevent the spread of the disease. Sampling of municipal wastewater has been studied as a plausible solution to detect pathogen spread, even from asymptomatic patients. However, many challenges exist in wastewater-based epidemiology such as identifying a representative sample for a population, determining the appropriate sample size, and establishing the right time and place for samples. In this work, a new approach to address these questions is assessed using stochastic modeling to represent wastewater sampling given a particular community of interest. Using estimates for various process parameters, inferences on the population infected are generated with Monte Carlo simulation output. A case study at the University of Oklahoma is examined to calibrate and evaluate the model output. Finally, extensions are provided for more efficient wastewater sampling campaigns in the future. This research provides greater insight into the effects of viral load, the percentage of the population infected, and sampling time on mean SARS-CoV-2 concentration through simulation. In doing so, an earlier warning of infection for a given population may be obtained and aid in reducing the spread of viruses. © 2023, The Author(s).

Pulmonary Findings of [18F]FDG PET/CT Images on Asymptomatic COVID-19 Patients.

During the coronavirus disease 2019 (COVID-19) pandemic, several case studies demonstrated that many asymptomatic patients with COVID-19 underwent fluorine-18 fluorodeoxyglucose ([18F]FDG) positron emission tomography/computed tomography (PET/CT) examination for various indications. However, there is a lack of literature to characterize the pattern of [18F]FDG PET/CT imaging on asymptomatic COVID-19 patients. Therefore, a systematic review to analyze the pulmonary findings of [18F]FDG PET/CT on asymptomatic COVID-19 patients was conducted. This systematic review was performed under the guidelines of PRISMA. PubMed, Medline, and Web of Science were used to search for articles for this review. Articles with the key words: "asymptomatic", "COVID-19", "[18F]FDG PET/CT", and "nuclear medicine" were searched for from 1 January 2020 to 20 May 2021. Thirty asymptomatic patients with COVID-19 were included in the eighteen articles. These patients had a mean age of 62.25 ± 14.85 years (male: 67.71 ± 12.00; female: 56.79 ± 15.81). [18F]FDG-avid lung lesions were found in 93.33% (28/30) of total patients. The major lesion was [18F]FDG-avid multiple ground-glass opacities (GGOs) in the peripheral or subpleural region in bilateral lungs, followed by the consolidation. The intensity of [18F]FDG uptake in multiple GGOs was 5.605 ± 2.914 (range from 2 to 12) for maximal standardized uptake value (SUVmax). [18F]FDG-avid thoracic lymph nodes (LN) were observed in 40% (12/40) of the patients. They mostly appeared in both mediastinal and hilar regions with an SUVmax of 5.8 ± 2.93 (range from 2.5 to 9.6). The [18F]FDG uptake was observed in multiple GGOs, as well as in the mediastinal and hilar LNs. These are common patterns in PET/CT of asymptomatic patients with COVID-19.

COVID-19 Metabolomic-Guided Amino Acid Therapy Protects from Inflammation and Disease Sequelae.

The outbreak of coronavirus disease 2019 (COVID-19) has caused a worldwide pandemic since 2019. A metabolic disorder is a contributing factor to deaths from COVID-19. However, the underlying mechanism of metabolic dysfunction in COVID-19 patients and the potential interventions are not elucidated. Here targeted plasma metabolomic is performed, and the metabolite profiles among healthy controls, and asymptomatic, moderate, and severe COVID-19 patients are compared. Among the altered metabolites, arachidonic acid and linolenic acid pathway metabolites are profoundly up-regulated in COVID-19 patients. Arginine biosynthesis, alanine, aspartate, and glutamate metabolism pathways are significantly disturbed in asymptomatic patients. In the comparison of metabolite variances among the groups, higher levels of l-citrulline and l-glutamine are found in asymptomatic carriers and moderate or severe patients at the remission stage. Furthermore, l-citrulline and l-glutamine combination therapy is demonstrated to effectively protect mice from coronavirus infection and endotoxin-induced sepsis, and is observed to efficiently prevent the occurrence of pulmonary fibrosis and central nervous system damage. Collectively, the data reveal the metabolite profile of asymptomatic COVID-19 patients and propose a potential strategy for COVID-19 treatment.

Effectiveness of Lianhua Qingwen Capsule in Treatment of Asymptomatic COVID-19 Patients: A Randomized, Controlled Multicenter Trial.

Background: Asymptomatic patients are unneglected sources in propagating transmission chain due to their high viral loads. However, treatments available based on symptoms seem not applicable to asymptomatic patients. In this study, the authors want to estimate the effectiveness of Lianhua Qingwen (LH) capsule on asymptomatic coronavirus disease 2019 (COVID-19) patients. Methods: A randomized controlled trial (RCT) was performed to explore the effectiveness and safety of LH capsule in treating asymptomatic COVID-19 patients. Patients were randomized to control group (isolated observation) and treatment group (LH, 4 capsules, thrice daily) for 14 days. The primary endpoints were the rate and time of nucleic acid turning negative during the isolation observation. Results: A total of 120 participants were included in the full analysis set (60 each in the control and treatment groups). Data showed that the rate of nucleic acid turning negative during the isolation observation in the treatment group was higher than that in the control group (rate difference: 21.66%, 95% confidence interval [CI]: 4.34 to 37.27, p = 0.0142). Patients in the treatment group have a shorter time of nucleic acid turning negative (7.5 vs. 14.5 days, p = 0.018). Moreover, the rate of clinical symptoms appearance in the treatment group was lower compared with that in the control group (rate difference: -31.67, 95% CI: -46.83 to -13.82, p = 0.0005). The proportion of confirmed mild and common cases in the treatment group was also lower (35.00% vs. 66.67%, p = 0.0005). No serious adverse events were documented. Conclusions: In this study, the authors illustrated that LH capsule is beneficial to asymptomatic COVID-19 patients. Considering the lack of interventions for treating asymptomatic COVID-19 patients at this stage, LH capsule could be considered as a choice. Chinese Clinical Trial Registry: ChiCTR2100042066.

ANDTi Virtual Assistant

Due of the current COVID-19 pandemic crises, there is a worldwide need for quick medical findings. Furthermore, due to a lack of medical facilities and medical practitioners' hectic schedules, several examinations must now be performed by the general public. Also because of the high rate of transmissibility of COVID-19, even asymptomatic patients can readily transfer the virus to others, faster detection is critical during the initial phase of COVID-19, which is early identification. The earlier a patient is detected;the better the virus's spread may be stopped and the patient can undergo proper treatment. As the nationwide vaccination process is in its later part, it is obvious that the government will uplift its regulations and the employees will have to return to their workplaces or offices. As a solution to this upcoming urgency the authors would like to propose a solution to identify COVID-19 patients in advance at corporate level. As an IoT based solution a device is supposed to be setup on top of each employee's desk, which in return will be used to monitor the oxygen level, temperature, and heartbeat rate of the employees. © 2022 IEEE.

Recognition of COVID-19 Pneumonia in Patients Performing Different Interventional Radiological Procedures of The Chest

Background: Coronavirus disease 2019 (COVID-19) was declared a global pandemic by the World Health Organization on March 11, 2020. Many individuals remain completely asymptomatic and can transmit the infection to the general population. The high rate of false-negative results of reverse transcription-polymerase chain reaction (RTPCR), particularly early in the course of the disease process, requires other tools to diagnose COVID-19 infection, with an important role of radiological imaging. Interventional radiology in many instances continues to provide frontline care during this pandemic and can overcome the unique challenges of safety while providing adequate and efficient highquality patient care. Objective: The aim of our study was to focus upon the detection of typical imaging features of COVID-19 infection for asymptomatic patients, performing the different interventional radiological procedures of the chest to avoid the spread of infection and thus influence better detection and further management. Patients and methods: In this cross-sectional study, we have 382 patients, coming for different interventional radiological procedures of the chest from May 2020 till 30 October 2021. Results: 35 (9.1%) patients had computed tomography (CT) features of COVID-19 pneumonia using CORADS classification. RT-PCR testing was performed in 28 cases while 7 patients showed negative results;four cases repeated the RT-PCR test and three of them became positive. The other 3 cases refused to repeat RT-PCR and were only isolated and carefully monitored. Conclusion: The radiology staff including interventional radiologists should be aware of the accidental discovery of imaging features of COVD-19 infection, before proceeding with the interventional procedure. CT chest is an important tool for detection of COVID-19 detection, even in asymptomatic patients. [ FROM AUTHOR] Copyright of Egyptian Journal of Hospital Medicine is the property of Egyptian Journal of Hospital Medicine 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.)

Artificial Neural Network based Automatic Prediction Unit for COVID 19 in Asymptomatic Patient

In this pandemic situation of COVID 19 virus attack in human race for the last few months the disease occurrence prediction and patient's condition monitoring is being a major thrust area in the global medical field by the researchers. The major problem of this disease is that the asymptomatic patient are acting as a carrier without knowledge. Which leads to a major threat in spreading the disease which even cause death in other people even after maintaining the social distancing. More over according to the research, rate of death is more in heart related disease affected patients. There is a vital need to detect cases at the early stages to minimize mortality especially in heart patients. In our work, we have designed and developed a trained Artificial Neural Network which can predict COVID 19 in asymptomatic patients and also can used for conditioning monitoring in COVID affected patients. Here we have used 2500 patients' details as training and testing data for the ANN network and 50 Symptoms as input variables. The Patients data are collected in Government Sivagangai Medical College and Hospital, Thirupathur village, Sivagangai district, Tamilnadu, India. © 2022 IEEE.

Time to Resolution of Infection in COVID-19 Patients: the Experience of a Tertiary Medical Center in Israel.

With the spread of coronavirus disease, reports have indicated that young patients are usually asymptomatic with a short convalescence period. The current study compared the time to resolution of infection in symptomatic and asymptomatic patients. Seventy-six patients aged 44.4 ± 23.3 years were admitted to the coronavirus disease 2019 (COVID-19) unit during the study period. Data were collected from patient records. Throat and nasal swabs for COVID-19 were collected for reverse transcriptase-polymerase chain reaction (RT-PCR). Time to resolution of infection was defined as the number of days from the date of the first COVID-19 positive outcome to the second consecutive negative PCR results. Most patients showed COVID-19 signs and symptoms (71.1%) between 1 and 6 days, and the rest were asymptomatic. No association was found between the time to resolution of infection and the presence of COVID-19 signs and symptoms (symptomatic: median [Md] 10.0, 95% confidence interval [CI] 8.4-11.6; asymptomatic: Md 15.0, 95% CI 10.5-15.5; P = 0.54). Age was not correlated with the number of COVID-19 signs and symptoms (r = 0.13, P = 0.37) or with the time to resolution of infection (r = 0.06, P = 0.58). In patients with mild to moderate symptoms, the time to resolution of infection from COVID-19 is not different from that in asymptomatic patients.

Early Prediction of COVID-19 Suspects Based on Fractional Order Optical Flow

Novel Coronavirus disease (COVID-19) is an infectious disease that has been declared as a pandemic by the World Health Organization. Both symptomatic, as well as asymptomatic patients, are equally likely capable of spreading the virus among the population. Therefore, a real-time tracing of COVID-19 suspects and their identification by a computer-based algorithm is a need of the current times, so that the spreaders could be isolated and the mushrooming should be halted. In this paper, we introduced a fractional order variational model for the early prediction and detection of COVID-19 suspects based on the CXR image sequence. The identification is performed in terms of optical flow color map. The proposed technique would be financially cheaper, require less time and manpower in comparison to the available techniques. The presented model keeps discontinuous information about texture and edges and offers a dense flow field for minuscule variations. The Grünwald-Letnikov derivative is employed for discretizing the complex fractional order partial derivatives. The validity of the model is verified through a variety of experimental results on various datasets. © 2021 IEEE.

Development of COVID-19 Prediction Models from Chest X-Ray Using Transfer Learning

Due to the outbreak of corona virus disease (COVID-19) globally, many countries are facing shortages of testing kits and medical resources. Moreover, the current COVID-19 swab test cannot easily perform due to asymptomatic patients. To assist the medical staff, few studies have proposed to detect and classify COVID-19 cases by analyzing radiological images. In this paper, we aim to develop an alternative method using chest X-ray images to provide an automatic and faster diagnosis. Convolutional neural network models that can detect the presence of COVID-19 and pneumonia infection from chest X-ray images are developed by exploiting transfer learning techniques. Three models were developed for comparison, the models yielded an accuracy of 97.3%, 98.2%, and 97.3% respectively. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

Demographic, Virological Characteristics and Prognosis of Asymptomatic COVID-19 Patients in South China.

BACKGROUND: Asymptomatic transmission is a major concern for SARS-CoV-2 community spread; however, little information is available on demographic, virological characteristics and prognosis of asymptomatic cases. METHODS: All COVID-19 patients hospitalized in Guangdong Province from September 1, 2020 to February 28, 2021, were included and were divided into asymptomatic and symptomaticgroup. The source country of all patients, clinical laboratory test results, the genotype of virus and the time of SARS-CoV-2 RNA turning negative or hospitalization were confirmed. RESULTS: Total 233 patients from 57 different countries or regions were included, with 83 (35.6%) asymptomatic and 150 (64.4%) symptomatic patients. Asymptomatic cases were younger (P = 0.019), lower rate in comorbidities (P = 0.021) such as hypertension (P = 0.083) and chronic liver disease (P = 0.045), lower PCT (P = 0.021), DDI (P < 0.001) and ALT (P = 0.029), but higher WBC count (P = 0.002) and lymphocyte (P = 0.011) than symptomatic patients. As for SARS-CoV-2 subtypes, patients infected with B.1.1 (53.8%), B.1.351 (81.8%) and B.1.524 (60%) are mainly asymptomatic, while infected with B, B.1, B.1.1.63, B.1.1.7, B.1.36, B.1.36.1, B.1.36.16, B.1.5 and B.6 were inclined to be symptomatic. Patients infected with variant B.1.351 and B.1.524 spent longer time in SARS-CoV-2 RNA turn negative (26 days, P = 0.085; 41 days, P = 0.007) and hospitalization (28 days, P = 0.085; 43 days, P = 0.004). CONCLUSIONS: The asymptomatic cases are prone to develop in patients with younger age, less comorbidities andinfected with B.1.1 and B.1.524 variants. More attention should be paid for lineage B.1.524 because it can significantly prolong the SARS-CoV-2 RNA negative conversion time and hospitalization in infected cases.

Analytical Performance of Quantitative DiaSorin Liaison SARS-COV-2 Antigen Test for the Asymptomatic Population.

Background: Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) antigen (Ag) tests have been widely employed to identify patients for a rapid diagnosis and pandemic control. Rapid lateral-flow techniques are currently the most used, but automated technologies have emerged as another viable alternative to molecular methods. We aimed to evaluate the analytical performance of the DiaSorin Liaison SARS-CoV-2 Ag test in asymptomatic population and close contacts, for its use as a tool in pandemic control efforts. Material and Methods: A retrospective study was conducted. A total of 861 samples were included, 291 (34%) were positive for SARS-CoV-2 with cycle threshold (Ct) <40, and 570 (66%) were negative. Results: A strong correlation was observed between reverse transcriptase-PCR (RT-PCR) Ct and Ag 50% Tissue Culture Infectious Dose per milliliter (TCID50/ml; r = 0.6486; p < 0.0001) and all RT-PCR negative samples tested negative for the 200 TCID50/ml SARS-Cov-2 Ag cutoff, i.e., a specificity of 100% was reached (95% CI: 99.4-100.0%). Samples with <25 Ct and/or >106 extrapolated copies/ml were reached a sensitivity of 100% (95% IC 97.0-100.0%). For intermediate viral loads (>105 extrapolated copies/ml or <30 Ct), the sensitivity value still exceeded 80%. As with other Ag methods, samples between 30 and 40 Ct could not be detected with a reliable sensitivity. Conclusions: The LIAISON® SARS-CoV-2 Ag assay displays an acceptable sensitivity and a very high specificity that is useful for detecting the presence of SARS-CoV-2 in nasal swabs (NPS) of asymptomatic population or to regular monitoring of risk groups in controlled settings. Additionally, the flexibility in processing different samples and in the sampling preparation process makes this test an option for its use in high throughput laboratories. Automated tests may facilitate result reporting and yield consistent data, while avoiding some of the pitfalls of rapid lateral-flow techniques, such as observer variability.

Forecast and evaluation of asymptomatic COVID-19 patients spreading in China.

In this paper, we propose a new SAIR model to depict the transmission dynamics of a novel coronavirus in China. We focus on the ability of asymptomatic COVID-19 patients to transmit and the potential impact of population movements on renewed outbreak transmission. Qualitative analysis of the model shows that when the basic productive number R 0 > 1 , the system will stabilize towards a unique endemic equilibrium and pass through a transcritical bifurcation around its disease-free equilibrium. Furthermore, by constructing an appropriate Lyapunov function, we prove that the disease-free equilibrium and endemic equilibrium are globally asymptotically stable under appropriate parameter conditions. Finally, some important results have been verified by numerical simulations.

Evaluation of Convolutional Neural Networks for COVID-19 Classification on Chest X-Rays

Early identification of patients with COVID-19 is essential to enable adequate treatment and to reduce the burden on the health system. The gold standard for COVID-19 detection is the use of RT-PCR tests. However, due to the high demand for tests, these can take days or even weeks in some regions of Brazil. Thus, an alternative for detecting COVID-19 is the analysis of Digital Chest X-rays (XR). Changes due to COVID-19 can be detected in XR, even in asymptomatic patients. In this context, models based on deep learning have great potential to be used as support systems for diagnosis or as screening tools. In this paper, we propose the evaluation of convolutional neural networks to identify pneumonia due to COVID-19 in XR. The proposed methodology consists of a preprocessing step of the XR, data augmentation, and classification by the convolutional architectures DenseNet121, InceptionResNetV2, InceptionV3, MovileNetV2, ResNet50, and VGG16 pre-trained with the ImageNet dataset. The obtained results for our methodology demonstrate that the VGG16 architecture presented a superior performance in the classification of XR, with an Accuracy of 85.11 %, Sensitivity of 85.25 %, Specificity of 85.16 %, F1-score of 85.03 %, and an AUC of 0.9758. © 2021, Springer Nature Switzerland AG.

EARLY RESPIRATORY OUTCOMES FOLLOWING CARDIAC SURGERY IN PATIENTS WITH COVID-19

Four patients underwent off-pump cardiac surgery and 21 underwent on-pump cardiac surgery with a median cardiopulmonary bypass time of 85 minutes (interquartile range (IQR, 50-147). B Conclusions: b Although early respiratory outcomes of asymptomatic COVID-19 patients who underwent early cardiac surgery appeared to be satisfactory, compared to the propensity-scored matched non-COVID group, the postoperative outcomes were worse, especially in the ICU readmitted patients. [Extracted from the article] Copyright of Critical Care Medicine is the property of Lippincott Williams & Wilkins 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.)