Detection of 2019 novel coronavirus (2019-nCoV) by real-time RT-PCR

Multiple assays in a real-time RT-PCR SARS-CoV-2 panel can mitigate the risk of loss of sensitivity by new genomic variants during the COVID-19 outbreak

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Publicly available RT-PCR Panels detect SARS-CoV-2 targeting more than one genomic region.

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Genetic variability observed until week 21 is predicted to have no effect on panel sensitivity.

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The QIAstat-Dx SARS-CoV-2 Panel remains highly sensitive despite the nucleotide variations.

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Combination of multiple assays in RT-PCR SARS-CoV-2 panels mitigate possible sensitivity loss.

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Genetic variability assessment is critical to monitor sensitivity and specificity of the assays.

Objectives

In this study, five SARS-CoV-2 PCR assay panels were evaluated against the accumulated genetic variability of the virus to assess the effect on sensitivity of the individual assays.

Design or methods

As of week 21, 2020, the complete set of available SARS-CoV-2 genomes from GISAID and GenBank databases were used in this study. SARS-CoV-2 primer sequences from publicly available panels (WHO, CDC, NMDC, and HKU) and QIAstat-Dx were included in the alignment, and accumulated genetic variability affecting any oligonucleotide annealing was annotated.

Results

A total of 11,627 (34.38%) genomes included single mutations affecting annealing of any PCR assay. Variations in 8,773 (25.94%) genomes were considered as high risk, whereas additional 2,854 (8.43%) genomes presented low frequent single mutations and were predicted to yield no impact on sensitivity. In case of the QIAstat-Dx SARS-CoV-2 Panel, 99.11% of the genomes matched with a 100% coverage all oligonucleotides, and critical variations were tested in vitro corroborating no loss of sensitivity.

Conclusions

This analysis stresses the importance of targeting more than one region in the viral genome for SARS-CoV-2 detection to mitigate the risk of loss of sensitivity due to the unknown mutation rate during this SARS-CoV-2 outbreak.

COVID-19 diagnostics in context

The coronavirus disease 2019 (COVID-19) pandemic has highlighted the need for different types of diagnostics, comparative validation of new tests, faster approval by federal agencies, and rapid production of test kits to meet global demands. In this Perspective, we discuss the utility and challenges of current diagnostics for COVID-19.

Clinical outcomes of hemodialysis patients infected with severe acute respiratory syndrome coronavirus 2 and impact of proactive chest computed tomography scans

Background

Coronavirus disease 2019 (COVID-19) is an emerging infectious disease that first manifested in humans in Wuhan, Hubei Province, China, in December 2019, and has subsequently spread worldwide.

Methods

We conducted a retrospective, single-center case series of the seven maintenance hemodialysis (HD) patients infected with COVID-19 at Zhongnan Hospital of Wuhan University from 13 January to 7 April 2020 and a proactive search of potential cases by chest computed tomography (CT) scans.

Results

Of 202 HD patients, 7 (3.5%) were diagnosed with COVID-19. Five were diagnosed by reverse transcription polymerase chain reaction (RT-PCR) because of compatible symptoms, while two were diagnosed by RT-PCR as a result of screening 197 HD patients without respiratory symptoms by chest CT. Thirteen of 197 patients had positive chest CT features and, of these, 2 (15%) were confirmed to have COVID-19. In COVID-19 patients, the most common features at admission were fatigue, fever and diarrhea [5/7 (71%) had all these]. Common laboratory features included lymphocytopenia [6/7 (86%)], elevated lactate dehydrogenase [3/4 (75%)], D-dimer [5/6 (83%)], high-sensitivity C-reactive protein [4/4 (100%)] and procalcitonin [5/5 (100%)]. Chest CT showed bilateral patchy shadows or ground-glass opacity in the lungs of all patients. Four of seven (57%) received oxygen therapy, one (14%) received noninvasive and invasive mechanical ventilation, five (71%) received antiviral and antibacterial drugs, three (43%) recieved glucocorticoid therapy and one (14%) received continuous renal replacement therapy. As the last follow-up, four of the seven patients (57%) had been discharged and three patients were dead.

Conclusions

Chest CT may identify COVID-19 patients without clear symptoms, but the specificity is low. The mortality of COVID-19 patients on HD was high.

SARS-CoV-2 infection in farmed minks, the Netherlands, April and May 2020

Respiratory disease and increased mortality occurred in minks on two farms in the Netherlands, with interstitial pneumonia and SARS-CoV-2 RNA in organ and swab samples. On both farms, at least one worker had coronavirus disease-associated symptoms before the outbreak. Variations in mink-derived viral genomes showed between-mink transmission and no infection link between the farms. Inhalable dust contained viral RNA, indicating possible exposure of workers. One worker is assumed to have attracted the virus from mink.

Epidemiological and Clinical Characteristics of Cases During the Early Phase of COVID-19 Pandemic: A Systematic Review and Meta-Analysis

Background: On 29th December 2019, a cluster of cases displaying the symptoms of a "pneumonia of unknown cause" was identified in Wuhan, Hubei province of China. This systematic review and meta-analysis aims to review the epidemiological and clinical characteristics of COVID-19 cases in the early phase of the COVID-19 pandemic. Methods: The search strategy involved peer-reviewed studies published between 1st January and 11th February 2020 in Pubmed, Google scholar and China Knowledge Resource Integrated database. Publications identified were screened for their title and abstracts according to the eligibility criteria, and further shortlisted by full-text screening. Three independent reviewers extracted data from these studies, and studies were assessed for potential risk of bias. Studies comprising non-overlapping patient populations, were included for qualitative and quantitative synthesis of results. Pooled prevalence with 95% confidence intervals were calculated for patient characteristics. Results: A total of 29 publications were selected after full-text review. This comprised of 18 case reports, three case series and eight cross-sectional studies on patients admitted from mid-December of 2019 to early February of 2020. A total of 533 adult patients with pooled median age of 56 (95% CI: 49-57) and a pooled prevalence of male of 60% (95% CI: 52-68%) were admitted to hospital at a pooled median of 7 days (95% CI: 7-7) post-onset of symptoms. The most common symptoms at admission were fever, cough and fatigue, with a pooled prevalence of 90% (95% CI: 81-97%), 58% (95% CI: 47-68%), and 50% (95% CI: 29-71%), respectively. Myalgia, shortness of breath, headache, diarrhea and sore throat were less common with pooled prevalence of 27% (95% CI: 20-36%), 25% (95% CI: 15-35%), 10% (95% CI: 7-13%), 8% (95% CI: 5-13%), and 7% (95% CI: 1-15%), respectively. ICU patients had a higher proportion of shortness of breath at presentation, as well as pre-existing hypertension, cardiovascular disease and COPD, compared to non-ICU patients in 2 studies (n = 179). Conclusion: This study highlights the key epidemiological and clinical features of COVID-19 cases during the early phase of the COVID-19 pandemic.

COVID-19 Infection Diagnosis: Potential Impact of Isothermal Amplification Technology to Reduce Community Transmission of SARS-CoV-2

The current coronavirus disease 2019 (COVID-19) pandemic is largely driven by community transmission, after 2019 novel Coronavirus (2019-nCoV or SARS-CoV-2) crosses the borders. To stop the spread, rapid testing is required at community clinics and hospitals. These rapid tests should be comparable with the standard PCR technology. Isothermal amplification technology provides an excellent alternative that is highly amenable to resource limited settings, where expertise and infrastructure to support PCR are not available. In this review, we provide a brief description of isothermal amplification technology, its potential and the gaps that need to be considered for SARS-CoV-2 detection. Among this emerging technology, loop-mediated amplification (LAMP), recombinase polymerase amplification (RPA) and Nicking enzyme-assisted reaction (NEAR) technologies have been identified as potential platforms that could be implemented at community level, without samples referral to a centralized laboratory and prolonged turnaround time associated with the standard COVID-19 RT-PCR test. LAMP, for example, has recently been shown to be comparable with PCR and could be performed in less than 30 min by non-laboratory staff, without RNA extractions commonly associated with PCR. Interestingly, NEAR (ID NOW™ COVID-19 (Abbott, IL, USA) was able to detect the virus in 5 min. More so, isothermal platforms are cost effective and could easily be scaled up to resource limited settings. Diagnostics developers, scientific community and commercial companies could consider this alternative method to help stop the spread of COVID-19.

Epidemiology and Clinical Symptoms Related to Seasonal Coronavirus Identified in Patients with Acute Respiratory Infections Consulting in Primary Care over Six Influenza Seasons (2014-2020) in France

There is currently debate about human coronavirus (HCoV) seasonality and pathogenicity, as epidemiological data are scarce. Here, we provide epidemiological and clinical features of HCoV patients with acute respiratory infection (ARI) examined in primary care general practice. We also describe HCoV seasonality over six influenza surveillance seasons (week 40 to 15 of each season) from the period 2014/2015 to 2019/2020 in Corsica (France). A sample of patients of all ages presenting for consultation for influenza-like illness (ILI) or ARI was included by physicians of the French Sentinelles Network during this period. Nasopharyngeal samples were tested for the presence of 21 respiratory pathogens by real-time RT-PCR. Among the 1389 ILI/ARI patients, 105 were positive for at least one HCoV (7.5%). On an annual basis, HCoVs circulated from week 48 (November) to weeks 14–15 (May) and peaked in week 6 (February). Overall, among the HCoV-positive patients detected in this study, HCoV-OC43 was the most commonly detected virus, followed by HCoV-NL63, HCoV-HKU1, and HCoV-229E. The HCoV detection rates varied significantly with age (p = 0.00005), with the age group 0–14 years accounting for 28.6% (n = 30) of HCoV-positive patients. Fever and malaise were less frequent in HCoV patients than in influenza patients, while sore throat, dyspnoea, rhinorrhoea, and conjunctivitis were more associated with HCoV positivity. In conclusion, this study demonstrates that HCoV subtypes appear in ARI/ILI patients seen in general practice, with characteristic outbreak patterns primarily in winter. This study also identified symptoms associated with HCoVs in patients with ARI/ILI. Further studies with representative samples should be conducted to provide additional insights into the epidemiology and clinical features of HCoVs.

Changes in SARS-CoV-2 Positivity Rate in Outpatients in Seattle and Washington State, March 1-April 16, 2020

This population epidemiology study characterizes trends in polymerase chain reaction (PCR) test positivity for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Washington State and the Seattle area between March 1 and April 16, 2020, before and after statewide physical distancing guidelines and stay-at-home orders.

Diagnostic performance of immunochromatography assay for rapid detection of IgM and IgG in coronavirus disease 2019

Serologic assays have been developed to detect infection with coronavirus disease 2019 (COVID‐19). This study was conducted to evaluate the diagnostic performance of an immunochromatography‐based assay of human serum for COVID‐19. The present study enrolled 149 subjects who had been tested by real‐time reverse transcription‐polymerase chain reaction (RT‐PCR) for COVID‐19 and were classified into two groups: 70 who were positive for COVID‐19 and 79 who were negative for COVID‐19 based on RT‐PCR. An immunochromatography‐based COVID‐19 immunoglobulin G (IgG)/immunoglobulin M (IgM) rapid test on the sera of the study population was applied to measure the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and receiver operating characteristic (ROC) curve compared to RT‐PCR, with a 95% confidence interval (CI). IgM or IgG antibodies were detected in 65 subjects (92.9%) classified as positive for COVID‐19 and in three subjects (3.8%) classified as negative for COVID‐19. The sensitivity and specificity percentages for IgM or IgG antibodies were 92.9% (95% CI: 84.1‐97.6) and 96.2% (95% CI: 89.3‐99.2), respectively, with 95.6% PPV and 93.8% NPV. The PPV rapidly improved with increasing disease prevalence from 19.8% to 96.1% in the presence of either IgM or IgG, while the NPV remained high with a change from 99.9% to 93.1%. The area under the ROC curve was 0.945 (95% CI: 0.903‐0.988) for subjects with either IgM or IgG positivity. In conclusion, the immunochromatography‐based COVID‐19 IgG/IgM rapid test is a useful and practical diagnostic assay for detection of COVID‐19, especially in the presence of IgM or IgG antibodies.

Immunochromatography‐based IgM or IgG antibodies for SARS‐CoV‐2 have higher 92.9% of sensitivity and 96.2% of specificity.

The positive predictive value for IgM or IgG antibodies markedly improved with increasing prevalence of COVID‐19.

Immunochromatography‐based IgG/IgM rapid test for SARS‐CoV‐2 is a useful diagnostic assay.

Two Detailed Plaque Assay Protocols for the Quantification of Infectious SARS-CoV-2

Severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2) has been identified as the causal agent of COronaVIrus Disease‐19 (COVID‐19), an atypical pneumonia‐like syndrome that emerged in December 2019. While SARS‐CoV‐2 titers can be measured by detection of viral nucleic acid, this method is unable to quantitate infectious virions. Measurement of infectious SARS‐CoV‐2 can be achieved by tissue culture infectious dose−50 (TCID₅₀), which detects the presence or absence of cytopathic effect in cells infected with serial dilutions of a virus specimen. However, this method only provides a qualitative infectious virus titer. Plaque assays are a quantitative method of measuring infectious SARS‐CoV‐2 by quantifying the plaques formed in cell culture upon infection with serial dilutions of a virus specimen. As such, plaque assays remain the gold standard in quantifying concentrations of replication‐competent lytic virions. Here, we describe two detailed plaque assay protocols to quantify infectious SARS‐CoV‐2 using different overlay and staining methods. Both methods have several advantages and disadvantages, which can be considered when choosing the procedure best suited for each laboratory. These assays can be used for several research purposes, including titration of virus stocks produced from infected cell supernatant and, with further optimization, quantification of SARS‐CoV‐2 in specimens collected from infected animals. © 2019 The Authors.

Basic Protocol: SARS‐CoV‐2 plaque assay using a solid double overlay method

Alternate Protocol: SARS‐CoV‐2 plaque assay using a liquid overlay and fixation‐staining method

Multiplexing primer/probe sets for detection of SARS-CoV-2 by qRT-PCR

BACKGROUND

The novel respiratory virus SARS-CoV-2, responsible for over 380,000 COVID-19 related deaths, has caused significant strain on healthcare infrastructure and clinical laboratories globally. The pandemic's initial challenges include broad diagnostic testing, consistent reagent supply lines, and access to laboratory instruments and equipment. In early 2020, primer/probe sets distributed by the CDC utilized the same fluorophore for molecular detection - requiring multiple assays to be run in parallel - consuming valuable and limited resources.

METHODS

Nasopharyngeal swabs submitted to UW Virology for SARS-CoV-2 clinical testing were extracted, amplified by our laboratory developed test (LDT) - a CDC-based quantitative reverse transcriptase PCR reaction - and analyzed for agreement between the multiplexed assay. Laboratory- confirmed respiratory infection samples were included to evaluate assay cross-reaction specificity.

RESULTS

Triplexing correctly identified SARS-CoV-2 in 98.4% of confirmed positive or inconclusive patient samples by single-plex LDT (n = 183/186). All 170 SARS-CoV-2 negative samples tested by single-plex LDT were negative by triplexing. Other laboratory-confirmed respiratory infections did not amplify for SARS-CoV-2 in the triplex reaction.

CONCLUSIONS

Multiplexing two virus-specific gene targets and an extraction control was found to be comparable to running parallel assays independently, while significantly improving assay throughput.

Effect of Environmental Conditions on SARS-CoV-2 Stability in Human Nasal Mucus and Sputum

We found that environmental conditions affect the stability of severe acute respiratory syndrome coronavirus 2 in nasal mucus and sputum. The virus is more stable at low-temperature and low-humidity conditions, whereas warmer temperature and higher humidity shortened half-life. Although infectious virus was undetectable after 48 hours, viral RNA remained detectable for 7 days.

Evaluation of the EDI enzyme linked immunosorbent assays for the detection of SARS-CoV-2 IgM and IgG antibodies in human plasma

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Evaluation of EDI^TM ELISAs for detection of SARS-CoV-2 IgM and IgG in human plasma.

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Antibodies were measured in 64 SARS-CoV-2 RT-PCR confirmed COVID-19 patients.

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with serial blood samples collected at different time points from symptom onset.

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In 200 healthy blood donors, and in 256 intensive care unit patients.

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High “true” vs. low “false” positivity rates for the SARS-CoV-2 IgM and IgG ELISAs.

Background

Besides SARS-CoV-2 RT-PCR testing, serological testing is emerging as additional option in COVID-19 diagnostics. Aim of this study was to evaluate novel immunoassays for detection of SARS-CoV-2 antibodies in human plasma.

Methods

Using EDI^TM Novel Coronavirus COVID-19 Enzyme Linked Immunosorbent Assays (ELISAs), we measured SARS-CoV-2 IgM and IgG antibodies in 64 SARS-CoV-2 RT-PCR confirmed COVID-19 patients with serial blood samples (n = 104) collected at different time points from symptom onset. Blood samples from 200 healthy blood donors and 256 intensive care unit (ICU) patients collected before the COVID-19 outbreak were also used.

Results

The positivity rates in the COVID-19 patients were 5.9% for IgM and 2.9% for IgG ≤ 5 days after symptom onset; Between day 5 and day 10 the positivity rates were 37.1% for IgM and 37.1% for IgG and rose to 76.4% for IgM and 82.4% for IgG after > 10–15 days. After 15–22 days the “true” positivity rates were 94.4% for IgM and 100% for IgG. The “false” positivity rates were 0.5% for IgM and 1.0% for IgG in the healthy blood donors, 1.6% for IgM and 1.2% for IgG in ICU patients.

Conclusions

This study shows high “true” vs. low “false” positivity rates for the EDI^TM SARS-CoV-2 IgM and IgG ELISAs.

Review of chest CT manifestations of COVID-19 infection

Coronavirus disease-19 (COVID-19) is a viral pandemic that started in China and has rapidly expanded worldwide. Typical clinical manifestations include fever, cough and dyspnea after an incubation period of 2-14 days. The diagnosis is based on RT-PCR test through a nasopharyngeal swab. Because of the pulmonary tropism of the virus, pneumonia is often encountered in symptomatic patients. Here, we review the pertinent clinical findings and the current published data describing chest CT findings in COVID-19 pneumonia, the diagnostic performance of CT for diagnosis, including differential diagnosis, as well the evolving role of imaging in this disease.

Subcutaneous administration of interferon beta-1a for COVID-19: A non-controlled prospective trial

Background

Recently, a new coronavirus spreads rapidly throughout the countries and resulted in a worldwide epidemic. Interferons have direct antiviral and immunomodulatory effects. Antiviral effects may include inhibition of viral replication, protein synthesis, virus maturation, or virus release from infected cells. Previous studies have shown that some coronaviruses are susceptible to interferons. The aim of this study was to evaluate the therapeutic effects of IFN-β-1a administration in COVID-19.

Methods

In this prospective non-controlled trial, 20 patients included. They received IFN-β-1a at a dose of 44 µg subcutaneously every other day up to 10 days. All patients received conventional therapy including Hydroxychloroquine, and lopinavir/ritonavir. Demographic data, clinical symptoms, virological clearance, and imaging findings recorded during the study.

Results

The mean age of the patients was 58.55 ± 13.43 years. Fever resolved in all patients during first seven days. Although other symptoms decreased gradually. Virological clearance results showed a significant decrease within 10 days. Imaging studies showed significant recovery after 14-day period in all patients. The mean time of hospitalization was 16.8 ± 3.4 days. There were no deaths or significant adverse drug reactions in the 14-day period.

Conclusions

Our findings support the use of IFN-β-1a in combination with hydroxychloroquine and lopinavir/ritonavir in the management of COVID-19.

Clinical trial registration number: IRCT20151227025726N12.

Laboratory diagnosis of SARS-CoV-2 - A review of current methods

At present the whole world is facing pandemic of the Coronavirus disease (COVID-19); caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This disease has rapidly spreads across the world from its origin of Wuhan, China and affected millions people worldwide and make them to remain in their homes. The knowledge of available laboratory methods is essential for early and correct diagnosis of COVID-19 to identify new cases as well as monitoring treatment of confirmed cases. In this review we aim to provide the updated information about selection of specimens and availability of various diagnostic methods and their utility with current findings for the laboratory diagnosis of SARS-CoV-2 infection. This will guide the healthcare professionals and government organizations to make strategy for establishing diagnostic facilities for SARS-CoV-2 infections.

When to Operate, Hesitate and Reintegrate: Society of Gynecologic Oncology Surgical Considerations during the COVID-19 Pandemic

The COVID-19 pandemic has challenged our ability to provide timely surgical care for our patients. In response, the U.S. Surgeon General, the American College of Srugeons, and other surgical professional societies recommended postponing elective surgical procedures and proceeding cautiously with cancer procedures that may require significant hospital resources and expose vulnerable patients to the virus. These challenges have particularly distressing for women with a gynecologic cancer diagnosis and their providers. Currently, circumstances vary greatly by region and by hospital, depending on COVID-19 prevalence, case mix, hospital type, and available resources. Therefore, COVID-19-related modifications to surgical practice guidelines must be individualized. Special consideration is necessary to evaluate the appropriateness of procedural interventions, recognizing the significant resources and personnel they require. Additionally, the pandemic may occur in waves, with patient demand for surgery ebbing and flowing accordingly. Hospitals, cancer centers and providers must prepare themselves to meet this demand. The purpose of this white paper is to highlight all phases of gynecologic cancer surgical care during the COVID-19 pandemic and to illustrate when it is best to operate, to hestitate, and reintegrate surgery. Triage and prioritization of surgical cases, preoperative COVID-19 testing, peri-operative safety principles, and preparations for the post-COVID-19 peak and surgical reintegration are reviewed.

Azole-Resistant COVID-19-Associated Pulmonary Aspergillosis in an Immunocompetent Host: A Case Report

COVID-19-associated pulmonary aspergillosis (CAPA) is a recently described disease entity affecting patients with severe pulmonary abnormalities treated in intensive care units. Delays in diagnosis contribute to a delayed start of antifungal therapy. In addition, the emergence of resistance to triazole antifungal agents puts emphasis on early surveillance for azole-resistant Aspergillus species. We present a patient with putative CAPA due to Aspergillus fumigatus with identification of a triazole-resistant isolate during therapy. We underline the challenges faced in the management of these cases, the importance of early diagnosis and need for surveillance given the emergence of triazole resistance.

Recent Advances in Molecular diagnosis curbing the COVID-19

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FDA has approved number of molecular tests for emergency use to address the pandemic confronting the world.

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Broad testing will help to identify infected person, enabling proper quarantining, treatment and control.

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No comparative analytical information is available about tests approved for emergency use.

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This is a summary of FDA emergency use authorization(EUA) recommended nucleic acid diagnostic modalities.

Towards reduction in bias in epidemic curves due to outcome misclassification through Bayesian analysis of time-series of laboratory test results: case study of COVID-19 in Alberta, Canada and Philadelphia, USA

BACKGROUND

Despite widespread use, the accuracy of the diagnostic test for SARS-CoV-2 infection is poorly understood. The aim of our work was to better quantify misclassification errors in identification of true cases of COVID-19 and to study the impact of these errors in epidemic curves using publicly available surveillance data from Alberta, Canada and Philadelphia, USA.

METHODS

We examined time-series data of laboratory tests for SARS-CoV-2 viral infection, the causal agent for COVID-19, to try to explore, using a Bayesian approach, the sensitivity and specificity of the diagnostic test.

RESULTS

Our analysis revealed that the data were compatible with near-perfect specificity, but it was challenging to gain information about sensitivity. We applied these insights to uncertainty/bias analysis of epidemic curves under the assumptions of both improving and degrading sensitivity. If the sensitivity improved from 60 to 95%, the adjusted epidemic curves likely falls within the 95% confidence intervals of the observed counts. However, bias in the shape and peak of the epidemic curves can be pronounced, if sensitivity either degrades or remains poor in the 60-70% range. In the extreme scenario, hundreds of undiagnosed cases, even among the tested, are possible, potentially leading to further unchecked contagion should these cases not self-isolate.

CONCLUSION

The best way to better understand bias in the epidemic curves of COVID-19 due to errors in testing is to empirically evaluate misclassification of diagnosis in clinical settings and apply this knowledge to adjustment of epidemic curves.

In vitro diagnostics of coronavirus disease 2019: Technologies and application

Laboratory-based diagnostic measures including virological and serological tests are essential for detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Real-time reverse transcription-polymerase chain reactions (rRT-PCR) can detect SARS-COV-2 by targeting open reading frame-1 antibodies (ORF1ab), envelope protein, nucleocapsid protein, RNA-dependent RNA polymerase genes, and the N1, N2, and N3 (3N) target genes. Therefore, rRT-PCR remains the primary method of diagnosing SARS-CoV-2 despite being limited by false-negative results, long turnaround, complex protocols, and a need for skilled personnel. Serological diagnosis of coronavirus disease 2019 (COVID-19) is simple and does not require complex techniques and equipment, rendering it suitable for rapid detection and massive screening. However, serological tests cannot confirm SARS-CoV-2, and results will be false-negative when antibody concentrations fall below detection limits. Balancing the increased use of laboratory tests, risk of testing errors, need for tests, burden on healthcare systems, benefits of early diagnosis, and risk of unnecessary exposure is a significant and persistent challenge in diagnosing COVID-19.

Activity and Health During the SARS-CoV2 Pandemic (ASAP): Study Protocol for a Multi-National Network Trial

Introduction: The worldwide spread of the novel coronavirus (SARS-CoV2) has prompted numerous countries to restrict public life. Related measures, such as limits on social gatherings, business closures, or lockdowns, are expected to considerably reduce the individual opportunities to move outside the home. As physical activity (PA) and sport participation significantly contribute to health, this study has two objectives. The objectives of this study are to assess changes in PA and well-being since the coronavirus outbreak in affected countries. Additionally, we will evaluate the impact of digital home-based exercise programs on PA as well as physical and mental health outcomes.

Method: A multinational network trial will be conducted with three planned phases (A, B, and C). Part A consists of administering a structured survey. It investigates changes in PA levels and health during the coronavirus outbreak and measures the preferences of the participants regarding online training programs. Part B is a two-armed randomized-controlled trial. Participants assigned to the intervention group (IG) will complete a digital 4-week home exercise training (live streaming via internet) guided by the survey results on content and time of program. The control group (CG) will not receive the program. Part C is 4-week access of both CG and IG to a digital archive of pre-recorded workouts from Part B. Similar to Part A, questionnaires will be used in both Part B and C to estimate the effects of exercise on measures of mental and physical health.

Results and Discussion: The ASAP project will provide valuable insights into the importance of PA during a global pandemic. Our initial survey is the first to determine how governmental confinement measures impact bodily and mental well-being. Based on the results, the intervention studies will be unique to address health problems potentially arising from losses in PA. If proven effective, the newly developed telehealth programs could become a significant and easy-to-distribute factor in combating PA decreases. Results of the study may hence guide policy makers on methods to maintain PA and health when being forced to restrict public life.

Study Register: DRKS00021273.

Laboratory Testing Methods for Novel Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2)

Following the first reports of coronavirus disease-19 (COVID-19) by China to the World Health Organization (WHO) on 31st December 2019, more than 4,302,774 novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) cases have been reported by authorities in 212 countries and territories by 12th May 2020. The outbreak and spread of COVID-19 worldwide, highlights the critical need for developing rapid and accurate diagnostic testing methods for emerging human coronavirus (CoV) infections. Testing is crucial to track the spread of disease during a pandemic, and to swiftly permit public health interventions including isolation, quarantine, and appropriate clinical management of afflicted individuals. The key components of viral diagnostic tests are (1) collection of the appropriate sample (blood, nasal swab, and throat swab), (2) availability of the genetic and proteomic sequences of the novel virus for analysis, and (3) rapid and accurate laboratory testing methods. The current gold standard for the molecular diagnosis of SARS-CoV-2 infection is the real-time reverse transcriptase-polymerase chain reaction (RT-PCR) for the qualitative and quantitative detection of viral nucleic acids. Other relevant laboratory methods include enzyme-linked immunoassays (EIA) for viral antibody and antigen detection, and serum viral neutralization (SVN) assays for antibody neutralization determination. The challenges faced in developing a diagnostic test for a novel pathogen are the ability to measure low viral loads for early detection, to provide low or no cross-reactivity with other viral strains and to deliver results rapidly. Several point-of-care molecular devices are currently being integrated for fast and accurate diagnosis of SARS-CoV-2 infections. This review discusses the current laboratory methods available to test for coronaviruses by focusing on the present COVID-19 outbreak.

Real-time reverse transcription loop-mediated isothermal amplification for rapid detection of SARS-CoV-2

Background

Highly sensitive real-time reverse transcription polymerase chain reaction (RT-qPCR) methods have been developed for the detection of SARS-CoV-2. However, they are costly. Loop-mediated isothermal amplification (LAMP) assay has emerged as a novel alternative isothermal amplification method for the detection of nucleic acid.

Methods

A rapid, sensitive and specific real-time reverse transcription LAMP (RT-LAMP) assay was developed for SARS-CoV-2 detection.

Results

This assay detected one copy/reaction of SARS-CoV-2 RNA in 30 min. Both the clinical sensitivity and specificity of this assay were 100%. The RT-LAMP showed comparable performance with RT-qPCR. Combining simplicity and cost-effectiveness, this assay is therefore recommended for use in resource resource-limited settings.

SARS-CoV-2: diagnostic and design conundrums in the context of male factor infertility

The question of whether SARS-CoV-2 (severe acute respiratory syndrome-related coronavirus-2 [SARS-CoV-2], leading to the COVID-19 infection) can be harboured in the testes and/or semen is currently unanswered. It is essential to understand the limitations of both antibody and real-time PCR tests in interpreting SARS-CoV-2 data in relation to analyses of semen and testicular tissue without appropriate controls. This article critically analyses the evidence so far on this, and the possible implications. The limitations of diagnostic tests in both sampling and testing methodologies, their validation and their relevance in interpreting data are also highlighted.

From the Common Cold to a Chaotic Contagion: the Potential for Coronaviruses To Cause Outbreaks of Severe Respiratory Disease Representing a Global Health Threat

Coronaviruses are a family of RNA viruses that typically cause mild respiratory disease in humans. However, over the past 20 years, three novel/variant coronaviruses have spilled over from animals into humans and have been associated with severe respiratory illness. In late 2002, severe acute respiratory syndrome (SARS) coronavirus (CoV) emerged in China and, over the following year, went on to cause approximately 8,100 cases and 774 deaths. A decade later, a cluster of severe pneumonia cases occurred on the Arabian Peninsula, marking the beginning of the Middle East respiratory syndrome (MERS)-CoV outbreak, which has resulted in nearly 2,500 confirmed cases and 850 deaths. Now in 2020, we are in the midst of a global pandemic caused by SARS-CoV-2, which, at the time of this writing, has claimed the lives of over 83,500 people and has been confirmed in over 1,500,000 cases. These outbreaks highlight the pathogenic potential of CoVs and the importance of infection prevention and diagnostic testing to reduce the spread of infectious diseases representing a global health threat.

Effect of Implementing Simulation Education on Health Care Worker Comfort With Nasopharyngeal Swabbing for COVID-19

OBJECTIVE

To determine if rapid implementation of simulation training for the nasopharyngeal swab procedure can increase provider confidence regarding procedure competency.

METHODS

A simulation training exercise was designed as a departmental initiative to improve competency performing nasopharyngeal swabs during the COVID-19 pandemic. Sixty-one health care workers attended teaching sessions led by the Department of Otorhinolaryngology on proper nasopharyngeal swab technique. After a brief lecture, participants practiced their swab technique using a high-fidelity airway simulation model. Pre- and postintervention self-evaluations were measured via standardized clinical competency questionnaires on a 5-point Likert scale ranging from "No knowledge, unable to perform" up to "Highly knowledgeable and confident, independent."

RESULTS

Forty-six participants in this study submitted pre- and postintervention self-assessments. Postintervention scores improved on average 1.41 points (95% CI, 1.10-1.73) out of 5 from a mean score of 3.13 to 4.54 (P < .0001). This reflects a large effect size with a Glass's delta value of 1.3.

DISCUSSION

Lecture coupled with simulation-based teaching can significantly improve health care workers' confidence in performing nasopharyngeal swabs. Proper training for frontline workers performing swabs for COVID-19 is essential to improving testing accuracy and can be achieved in a simple and timely manner.

IMPLICATIONS FOR PRACTICE

To meet the testing needs of the growing pandemic, many health care workers who are unfamiliar with nasopharyngeal swabs have been asked to perform this test. Simulation-based teaching sessions may improve health care workers' confidence and help prevent false-negative results. This intervention is easily reproducible in any setting where frequent nasopharyngeal swab testing occurs.

LEVEL OF EVIDENCE/STUDY DESIGN

Prospective cohort study.

Comparison of diagnostic accuracies of rapid serological tests and ELISA to molecular diagnostics in patients with suspected coronavirus disease 2019 presenting to the hospital

Objectives

To assess the diagnostic performance of rapid lateral flow immunochromatographic assays (LFAs) compared with an ELISA and nucleic acid amplification tests (NATs) in individuals with suspected coronavirus disease 2019 (COVID-19).

Methods

Patients presenting to a Dutch teaching hospital were eligible between 17 March and 10 April 2020, when they had respiratory symptoms that were suspected for COVID-19. The performances of six different LFAs were evaluated in plasma samples obtained on corresponding respiratory sample dates of NATs testing. Subsequently, the best performing LFA was evaluated in 228 patients and in 50 sera of a historical patient control group.

Results

In the pilot analysis, sensitivity characteristics of LFA were heterogeneous, ranging from 2/20 (10%; 95% CI 0%–23%) to 11/20 (55%; 95% CI 33%–77%). In the total cohort, Orient Gene Biotech COVID-19 IgG/IgM Rapid Test LFA had a sensitivity of 43/99 (43%; 95% CI 34%–53%) and specificity of 126/129 (98%; 95% CI 95%–100%). Sensitivity increased to 31/52 (60%; 95% CI 46%–73%) in patients with at least 7 days of symptoms, and to 21/33 (64%; 95% CI 47%–80%) in patients with C-reactive protein (CRP) ≥100 mg/L. Sensitivity and specificity of Wantai SARS-CoV-2 Ab ELISA was 59/95 (62%; 95% CI 52%–72%) and 125/128 (98%; 95% CI 95%–100%) in all patients, respectively, but sensitivity increased to 38/48 (79%; 95% CI 68%–91%) in patients with at least 7 days of symptoms.

Conclusions

There is large variability in diagnostic test performance between rapid LFAs, but overall limited sensitivity and high specificity in acutely admitted patients. Sensitivity improved in patients with longer existing symptoms or high CRP. LFAs should only be considered as additional triage tools when these may lead to the improvement of hospital logistics.

Diagnostic Testing for Severe Acute Respiratory Syndrome-Related Coronavirus 2: A Narrative Review

Diagnostic testing to identify persons infected with severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) infection is central to control the global pandemic of COVID-19 that began in late 2019. In a few countries, the use of diagnostic testing on a massive scale has been a cornerstone of successful containment strategies. In contrast, the United States, hampered by limited testing capacity, has prioritized testing for specific groups of persons. Real-time reverse transcriptase polymerase chain reaction-based assays performed in a laboratory on respiratory specimens are the reference standard for COVID-19 diagnostics. However, point-of-care technologies and serologic immunoassays are rapidly emerging. Although excellent tools exist for the diagnosis of symptomatic patients in well-equipped laboratories, important gaps remain in screening asymptomatic persons in the incubation phase, as well as in the accurate determination of live viral shedding during convalescence to inform decisions to end isolation. Many affluent countries have encountered challenges in test delivery and specimen collection that have inhibited rapid increases in testing capacity. These challenges may be even greater in low-resource settings. Urgent clinical and public health needs currently drive an unprecedented global effort to increase testing capacity for SARS-CoV-2 infection. Here, the authors review the current array of tests for SARS-CoV-2, highlight gaps in current diagnostic capacity, and propose potential solutions.

Tocilizumab administration in a refractory case of COVID-19

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Pathophysiological studies have demonstrated the role of inflammatory mediators in COVID-19 pneumonia.

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In some COVID-19 cases, especially those with impaired immune function, an uncontrolled immune response that triggers an overproduction of immune cells and their signaling molecules occurs.

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Cytokine release syndrome may be the underlying pathophysiology of refractory cases.

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Tocilizumab, as an IL-6 antagonist, may have a promising role in the cytokine release syndrome that occurs in COVID-19.

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Clinicians should be aware of the precautions and contraindications of tocilizumab.

Interventions to mitigate early spread of SARS-CoV-2 in Singapore: a modelling study

BACKGROUND

Since the coronavirus disease 2019 outbreak began in the Chinese city of Wuhan on Dec 31, 2019, 68 imported cases and 175 locally acquired infections have been reported in Singapore. We aimed to investigate options for early intervention in Singapore should local containment (eg, preventing disease spread through contact tracing efforts) be unsuccessful.

METHODS

We adapted an influenza epidemic simulation model to estimate the likelihood of human-to-human transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in a simulated Singaporean population. Using this model, we estimated the cumulative number of SARS-CoV-2 infections at 80 days, after detection of 100 cases of community transmission, under three infectivity scenarios (basic reproduction number [R₀] of 1·5, 2·0, or 2·5) and assuming 7·5% of infections are asymptomatic. We first ran the model assuming no intervention was in place (baseline scenario), and then assessed the effect of four intervention scenarios compared with a baseline scenario on the size and progression of the outbreak for each R₀ value. These scenarios included isolation measures for infected individuals and quarantining of family members (hereafter referred to as quarantine); quarantine plus school closure; quarantine plus workplace distancing; and quarantine, school closure, and workplace distancing (hereafter referred to as the combined intervention). We also did sensitivity analyses by altering the asymptomatic fraction of infections (22·7%, 30·0%, 40·0%, and 50·0%) to compare outbreak sizes under the same control measures.

FINDINGS

For the baseline scenario, when R₀ was 1·5, the median cumulative number of infections at day 80 was 279 000 (IQR 245 000-320 000), corresponding to 7·4% (IQR 6·5-8·5) of the resident population of Singapore. The median number of infections increased with higher infectivity: 727 000 cases (670 000-776 000) when R₀ was 2·0, corresponding to 19·3% (17·8-20·6) of the Singaporean population, and 1 207 000 cases (1 164 000-1 249 000) when R₀ was 2·5, corresponding to 32% (30·9-33·1) of the Singaporean population. Compared with the baseline scenario, the combined intervention was the most effective, reducing the estimated median number of infections by 99·3% (IQR 92·6-99·9) when R₀ was 1·5, by 93·0% (81·5-99·7) when R₀ was 2·0, and by 78·2% (59·0 -94·4) when R₀ was 2·5. Assuming increasing asymptomatic fractions up to 50·0%, up to 277 000 infections were estimated to occur at day 80 with the combined intervention relative to 1800 for the baseline at R₀ of 1·5.

INTERPRETATION

Implementing the combined intervention of quarantining infected individuals and their family members, workplace distancing, and school closure once community transmission has been detected could substantially reduce the number of SARS-CoV-2 infections. We therefore recommend immediate deployment of this strategy if local secondary transmission is confirmed within Singapore. However, quarantine and workplace distancing should be prioritised over school closure because at this early stage, symptomatic children have higher withdrawal rates from school than do symptomatic adults from work. At higher asymptomatic proportions, intervention effectiveness might be substantially reduced requiring the need for effective case management and treatments, and preventive measures such as vaccines.

FUNDING

Singapore Ministry of Health, Singapore Population Health Improvement Centre.

Epidemiological and initial clinical characteristics of patients with family aggregation of COVID-19

BACKGROUND

Since December 2019, a new outbreak of the coronavirus disease 2019 (COVID-19) in Wuhan (Hubei, China) and rapidly spread throughout China, however, confirmed cases are still increasing worldwide.

OBJECTIVES

To investigate the epidemiological history and initial clinical characteristics of 10 patients with family aggregation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Western Chongqing, China.

STUDY DESIGN

Ten patients positive for SARS-CoV-2 nucleic acid detection by real time Reverse Transcription-Polymerase Chain Reaction (RT-PCR), were collected from The People's Hospital of Dazu District, Chongqing. Epidemiological data and laboratory and imaging results were collected on the first day of admission, and analyzed based on the Diagnosis and Treatment Guideline for COVID-19 (5th edition, China).

RESULTS

Of the 10 cases, case A had a history of a temporary stay in Wuhan and transmitted the virus to the others through family gathering, living together, and sharing vehicles. The average age was 56.5 years (± 11.16), six patients were males, and the incubation period was 2-14 days. Dry cough was the main symptom, followed by fever and fatigue. Most patients were clinically classified as ordinary-type, with three cases being severe-type. Chest computed tomography results were nonspecific, mainly with ground-glass attenuation and/or shadow images. Extensive lesion distribution was seen in severe cases. CD4+ lymphocyte counts were 61, 180, and 348 cells/uL in severe-type patients, respectively. Notably, viral nucleic acid values in nasopharyngeal swabs were lower (19, 25, and 26) than those of ordinary-type patients, suggesting a higher viral load. Neutrophil-lymphocyte ratio (NLR) was also higher in severe-type patients CONCLUSIONS: Initial examination results of lower CD4+ lymphocyte counts and RT-PCR-CT values coupled with higher NLR may indicate the severity of COVID-19 infection for these family clusters.

Development of Reverse Transcription Loop-Mediated Isothermal Amplification Assays Targeting Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)

The coronavirus disease 2019 (COVID-19) pandemic now has >2,000,000 confirmed cases worldwide. COVID-19 is currently diagnosed using quantitative RT-PCR methods, but the capacity of quantitative RT-PCR methods is limited by their requirement of high-level facilities and instruments. We developed and evaluated reverse transcription loop-mediated isothermal amplification (RT-LAMP) assays to detect genomic RNA of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative virus of COVID-19. RT-LAMP assays reported in this study can detect as low as 100 copies of SARS-CoV-2 RNA. Cross-reactivity of RT-LAMP assays to other human coronaviruses was not observed. A colorimetric detection method was adapted for this RT-LAMP assay to enable higher throughput.

COVID-19: Key Concepts for the Surgeon

In view of the current pandemic by SARS-CoV-2 it deems essential to understand the key concepts about the infection: its epidemiological origin, presentation, clinical course, diagnosis and treatment (still experimental in many cases). The knowledge about the virus is still limited, but as the pandemic progresses and the physiopathology of the disease is understood, new evidence is being massively published. Surgical specialists are facing an unprecedented situation: they must collaborate in the ER or medical wards attending these patients, while still needing to make decisions about surgical patients with probable COVID-19. The present narrative review aims to summarize the most relevant aspects and synthetize concepts on COVID-19 for surgeons.

Diarrhea: An underestimated symptom in Coronavirus disease 2019

In a retrospective study in the Nord Franche-Comté hospital conducted between March 1st and March 17th 2020, and compared to the review of Li et al., diarrhea was a main symptom in patients with COVID-19. Out of the 114 patients, 55 (48%) had diarrhea; it was the fifth most common symptom. In the group of patients with diarrhea, the median age was 56 years (±18) and 32 (58%) were female. Only 2 patients (3.6%) had a past history of inflammatory bowel disease. Fifty-six percent of patients (n=30/54) were hospitalised. Diarrhea appeared 4.5 days (±1.8) after the onset of the first other symptoms in COVID-19. Of the 55 patients with diarrhea, 29 (52.7%) had at least one simultaneous gastrointestinal (GI) symptom other than diarrhea. Twenty-five patients (45.5%) had nausea, 19 patients (34.5%) had abdominal pain and 9 (16.3%) had vomiting. Myalgia, sore throat, sneezing and the other GI symptoms were statistically more frequent in the group with diarrhea than in the group without diarrhea (P<0.05).

Elective, Non-urgent Procedures and Aesthetic Surgery in the Wake of SARS-COVID-19: Considerations Regarding Safety, Feasibility and Impact on Clinical Management

BACKGROUND

The worldwide spread of a novel coronavirus disease (COVID-19) has led to a near total stop of non-urgent, elective surgeries across all specialties in most affected countries. In the field of aesthetic surgery, the self-imposed moratorium for all aesthetic surgery procedures recommended by most international scientific societies has been adopted by many surgeons worldwide and resulted in a huge socioeconomic impact for most private practices and clinics. An important question still unanswered in most countries is when and how should elective/aesthetic procedures be scheduled again and what kind of organizational changes are necessary to protect patients and healthcare workers when clinics and practices reopen. Defining manageable, evidence-based protocols for testing, surgical/procedural risk mitigation and clinical flow management/contamination management will be paramount for the safety of non-urgent surgical procedures.

METHODS

We conducted a MEDLINE/PubMed research for all available publications on COVID-19 and surgery and COVID-19 and anesthesia. Articles and referenced literature describing possible procedural impact factors leading to exacerbation of the clinical evolution of COVID-19-positive patients were identified to perform risk stratification for elective surgery. Based on these impact factors, considerations for patient selection, choice of procedural complexity, duration of procedure, type of anesthesia, etc., are discussed in this article and translated into algorithms for surgical/anesthesia risk management and clinical management. Current recommendations and published protocols on contamination control, avoidance of cross-contamination and procedural patient flow are reviewed. A COVID-19 testing guideline protocol for patients planning to undergo elective aesthetic surgery is presented and recommendations are made regarding adaptation of current patient information/informed consent forms and patient health questionnaires.

CONCLUSION

The COVID-19 crisis has led to unprecedented challenges in the acute management of the crisis, and the wave only recently seems to flatten out in some countries. The adaptation of surgical and procedural steps for a risk-minimizing management of potential COVID-19-positive patients seeking to undergo elective aesthetic procedures in the wake of that wave will present the next big challenge for the aesthetic surgery community. We propose a clinical algorithm to enhance patient safety in elective surgery in the context of COVID-19 and to minimize cross-contamination between healthcare workers and patients. New evidence-based guidelines regarding surgical risk stratification, testing, and clinical flow management/contamination management are proposed. We believe that only the continuous development and broad implementation of guidelines like the ones proposed in this paper will allow an early reintegration of all aesthetic procedures into the scope of surgical care currently performed and to prepare the elective surgical specialties better for a possible second wave of the pandemic.

LEVEL OF EVIDENCE V

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Epidemiology and clinical features of COVID-19: A review of current literature

Coronavirus disease 2019 is a pandemic influencing the first half of the year 2020. The virus has rapidly spread to many countries. Studies are rapidly published to share information regarding epidemiology, clinical and diagnostic patterns, and prognosis. The following review condenses the surge of information into an organized format.

Covid-19 pandemic by the "real-time" monitoring: the Tunisian case and lessons for global epidemics in the context of 3PM strategies

Covid-19 is neither the first nor the last viral epidemic which societies around the world are, were and will be affected by. Which lessons should be taken from the current pandemic situation? The Covid-19 disease is still not well characterised, and many research teams all over the world are working on prediction of the epidemic scenario, protective measures to populations and sub-populations, therapeutic and vaccination issues, amongst others. Contextually, countries with currently low numbers of Covid-19-infected individuals such as Tunisia are intended to take lessons from those countries which already reached the exponential phase of the infection distribution as well as from those which have the exponential phase behind them and record a minor number of new cases such as China. To this end, in Tunisia, the pandemic wave has started with a significant delay compared with Europe, the main economic partner of the country. In this paper, we do analyse the current pandemic situation in this country by studying the infection evolution and considering potential protective strategies to prevent a pandemic scenario. The model is predictive based on a large number of undetected Covid-19 cases that is particularly true for some country regions such as Sfax. Infection distribution and mortality rate analysis demonstrate a highly heterogeneous picture over the country. Qualitative and quantitative comparative analysis leads to a conclusion that the reliable "real-time" monitoring based on the randomised laboratory tests is the optimal predictive strategy to create the most effective evidence-based preventive measures. In contrast, lack of tests may lead to incorrect political decisions causing either unnecessary over-protection of the population that is risky for a long-term economic recession, or under-protection of the population leading to a post-containment pandemic rebound. Recommendations are provided in the context of advanced predictive, preventive and personalised (3P) medical approach.

SARS-CoV-2 infection in farmed minks, the Netherlands, April and May 2020

Respiratory disease and increased mortality occurred in minks on two farms in the Netherlands, with interstitial pneumonia and SARS-CoV-2 RNA in organ and swab samples. On both farms, at least one worker had coronavirus disease-associated symptoms before the outbreak. Variations in mink-derived viral genomes showed between-mink transmission and no infection link between the farms. Inhalable dust contained viral RNA, indicating possible exposure of workers. One worker is assumed to have attracted the virus from mink.

Association Between Hypoxemia and Mortality in Patients With COVID-19

OBJECTIVE

To identify markers associated with in-hospital death in patients with coronavirus disease 2019 (COVID-19)-associated pneumonia.

PATIENTS AND METHODS

A retrospective cohort study was conducted of 140 patients with moderate to critical COVID-19-associated pneumonia requiring oxygen supplementation admitted to the hospital from January 28, 2020, through February 28, 2020, and followed up through March 13, 2020, in Union Hospital, Wuhan, China. Oxygen saturation (SpO2) and other measures were tested as predictors of in-hospital mortality in survival analysis.

RESULTS

Of 140 patients with COVID-19-associated pneumonia, 72 (51.4%) were men, with a median age of 60 years. Patients with SpO2 values of 90% or less were older and were more likely to be men, to have hypertension, and to present with dyspnea than those with SpO2 values greater than 90%. Overall, 36 patients (25.7%) died during hospitalization after median 14-day follow-up. Higher SpO2 levels after oxygen supplementation were associated with reduced mortality independently of age and sex (hazard ratio per 1-U SpO2, 0.93; 95% CI, 0.91 to 0.95; P<.001). The SpO2 cutoff value of 90.5% yielded 84.6% sensitivity and 97.2% specificity for prediction of survival. Dyspnea was also independently associated with death in multivariable analysis (hazard ratio, 2.60; 95% CI, 1.24 to 5.43; P=.01).

CONCLUSION

In this cohort of patients with COVID-19, hypoxemia was independently associated with in-hospital mortality. These results may help guide the clinical management of patients with severe COVID-19, particularly in settings requiring strategic allocation of limited critical care resources.

TRIAL REGISTRATION

Chictr.org.cn Identifier: ChiCTR2000030852.

Rapid asymptomatic transmission of COVID-19 during the incubation period demonstrating strong infectivity in a cluster of youngsters aged 16-23 years outside Wuhan and characteristics of young patients with COVID-19: A prospective contact-tracing study

BACKGROUND

The outbreak of coronavirus-disease-2019 (COVID-19) has rapidly spread to many places outside Wuhan. Previous studies on COVID-19 mostly included older hospitalized-adults. Little information on infectivity among and characteristics of youngsters with COVID-19 is available.

METHODS

A cluster of 22 close-contacts of a 22-year-old male (Patient-Index) including youngsters with laboratory-confirmed COVID-19 and hospitalized close-contacts testing negative for severe-acute-respiratory-syndrome-coronavirus-2 (SARS-CoV-2) in Anhui Province, China was prospectively-traced.

RESULTS

Since January 23, 2020, we enrolled a cluster of eight youngsters with COVID-19 (median age [range], 22 [16-23] years; six males) originating from Patient-Index returning from Wuhan to Hefei on January 19. Patient-Index visited his 16-year-old female cousin in the evening on his return, and met 15 previous classmates in a get-together on January 21. He reported being totally asymptomatic and were described by all his contacts as healthy on January 19-21. His very first symptoms were itchy eyes and fever developed at noon and in the afternoon on January 22, respectively. Seven youngsters (his cousin and six classmates) became infected with COVID-19 after a-few-hour-contact with Patient-Index. None of the patients and contacts had visited Wuhan (except Patient-Index), or had any exposure to wet-markets, wild-animals, or medical-institutes within three months. For affected youngsters, the median incubation-period was 2 days (range, 1-4). The median serial-interval was 1 day (range, 0-4). Half or more of the eight COVID-19-infected youngsters had fever, cough, sputum production, nasal congestion, and fatigue on admission. All patients had mild conditions. Six patients developed pneumonia (all mild; one bilateral) on admission. As of February 20, four patients were discharged.

CONCLUSIONS

SARS-CoV-2-infection presented strong infectivity during the incubation-period with rapid transmission in this cluster of youngsters outside Wuhan. COVID-19 developed in these youngsters had fast onset and various nonspecific atypical manifestations, and were much milder than in older patients as previously reported.

Multicentre comparison of quantitative PCR-based assays to detect SARS-CoV-2, Germany, March 2020

Containment strategies and clinical management of coronavirus disease (COVID-19) patients during the current pandemic depend on reliable diagnostic PCR assays for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here, we compare 11 different RT-PCR test systems used in seven diagnostic laboratories in Germany in March 2020. While most assays performed well, we identified detection problems in a commonly used assay that may have resulted in false-negative test results during the first weeks of the pandemic.