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1.
Sci Rep ; 12(1): 3351, 2022 03 01.
Article in English | MEDLINE | ID: covidwho-1721581

ABSTRACT

Severe acute respiratory coronavirus 2 (SARS-CoV-2) has spread globally since its emergence in 2019. Most SARS-CoV-2 infections generate immune responses leading to rising levels of immunoglobulins (Ig) M, A and G which can be detected using diagnostic tests including enzyme-linked immunosorbent assays (ELISA). Whilst implying previous SARS-CoV-2 infection, the detection of Ig by ELISA does not guarantee the presence of neutralising antibodies (NAb) that can prevent the virus infecting cells. Plaque reduction neutralisation tests (PRNT) detect NAb, but are not amenable to mass testing as they take several days and require use of SARS-CoV-2 in high biocontainment laboratories. We evaluated the ability of IgG and IgM ELISAs targeting SARS-CoV-2 spike subunit 1 receptor binding domain (S1-RBD), and spike subunit 2 (S2) and nucleocapsid protein (NP), at predicting the presence and magnitude of NAb determined by PRNT. IgG S2 + NP ELISA was 96.8% [95% CI 83.8-99.9] sensitive and 88.9% [95% CI 51.8-99.7] specific at predicting the presence of NAbs (PRNT80 > 1:40). IgG and IgM S1-RBD ELISAs correlated with PRNT titre, with higher ELISA results increasing the likelihood of a robust neutralising response. The IgM S1-RBD assay can be used as a rapid, high throughput test to approximate the magnitude of NAb titre.


Subject(s)
Antibodies, Viral/immunology , COVID-19/immunology , Immunoglobulin G/immunology , Immunoglobulin M/immunology , Neutralization Tests , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Aged , Enzyme-Linked Immunosorbent Assay , Female , Humans , Male , Middle Aged
2.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-313906

ABSTRACT

Severe acute respiratory coronavirus 2 (SARS-CoV-2) has spread globally since its emergence in 2019. Most SARS-CoV-2 infections generate immune responses leading to rising levels of immunoglobulins (Ig) M, A and G which can be detected using diagnostic tests including enzyme-linked immunosorbent assays (ELISA). Whilst implying previous SARS-CoV-2 infection, the detection of Ig by ELISA does not guarantee the presence of neutralising antibodies (NAb) that can prevent the virus infecting cells. Plaque reduction neutralisation tests (PRNT) detect NAb but are not amenable to mass testing as they take several days and require use of viable SARS-CoV-2 in high biocontainment laboratories. We evaluated the ability of IgG and IgM ELISAs targeting SARS-CoV-2 spike subunit 1 (S1) and nucleocapsid protein (NP) at predicting the presence and magnitude of NAb determined by PRNT. SARS-CoV-2 IgG ELISA correlated well with NAb and was highly sensitive (93.8% [95% CI 79.2–99.2]) and specific (88.9% [95% CI 51.8–99.7%]) at predicting the presence of NAb. There was not a strong correlation between IgM ELISA and PRNT result. IgG ELISA provides a useful, high throughput method of predicting the presence of neutralising antibodies, with higher ELISA results increasing the likelihood of having a greater NAb titre.

3.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-308904

ABSTRACT

Background: The coronavirus disease 2019 (COVID-19) pandemic has highlighted the reliance on antigen detection rapid diagnostic tests (Ag-RDTs). Their evaluation at point of use is a priority. Methods: : Here, we report a multi-centre evaluation of the analytical sensitivity, specificity, and clinical accuracy of the Mologic COVID-19 Ag-RDT by comparing to reverse transcriptase polymerase chain reaction (RT-qPCR) results from individuals with and without COVID-19 symptoms. Participants had attended hospitals in Merseyside, hospital and ambulance services in Yorkshire, and drive-through testing facilities in Northumberland, UK. Results: : The limit of detection of the Mologic COVID-19 Ag-RDT was 5.0 x 102 pfu/ml in swab matrix with no cross-reactivity and interference for any other pathogens tested. A total of 347 participants were enrolled from 26th of November 2020 to 15th of February 2021 with 39.2% (CI 34.0-44.6) testing RT-qPCR positive for SARS-CoV-2. The overall sensitivity and specificity of the Mologic Ag-RDT compared to the reference SARS-CoV-2 RT-qPCR were 85.0% (95% CI 78.3-90.2) and 97.8% (95.0-99.3), respectively. Sensitivity was stratified by RT-qPCR cycle threshold (Ct) and 98.4% (91.3-100) of samples with a Ct less than 20 and 93.2% (86.5-97.2) of samples with a Ct less than 25 were detected using the Ag-RDT. Clinical accuracy was stratified by sampling strategy, swab type and clinical presentation. Mologic COVID-19 Ag-RDT demonstrated highest sensitivity with nose/throat swabs compared with throat or nose swabs alone;however, the differences were not statistically significant. Conclusions: : Overall, the Mologic test had high diagnostic accuracy across multiple different settings, different demographics, and on self-collected swab specimens. These findings suggest the Mologic rapid antigen test may be deployed effectively across a range of use settings.

4.
2021.
Preprint in English | Other preprints | ID: ppcovidwho-294350

ABSTRACT

Background Accurate, affordable, and rapid point-of-care (PoC) diagnostics are critical to the global control and management of the COVID-19 pandemic. The current standard for accurate diagnosis of SARS-CoV-2 is laboratory-based reverse transcription polymerase chain reaction (RT-PCR). Here, we report a preliminary prospective performance evaluation of the QuantuMDx Q-POC™ SARS CoV-2 RT-PCR assay. Methods Between November 2020 and March 2021, we obtained 49 longitudinal nose and throat swabs from 29 individuals hospitalised with RT-PCR confirmed COVID-19 at St George’s NHS Foundation Trust, London (UK). In addition, we obtained 101 mid nasal swabs from healthy volunteers in June 2021. We then used these samples to evaluate the Q-POC™ SARS-CoV-2 RT-PCR assay. The primary analysis was to compare the sensitivity and specificity of the Q-POC™ test against a reference laboratory-based RT-PCR assay. Results The overall sensitivity of the Q-POC™ test compared with the reference test was 96.88% (83.78%-99.92% CI) for a cycle threshold (Ct) cut-off value for the reference test of 35 and 80.00% (64.35% to 90.95% CI) without altering the reference test’s Ct cut-off value of 40. Conclusions The Q-POC™ test is a sensitive, specific and rapid point-of-care test for SARS-CoV-2 at a reference Ct cut-off value of 35. The Q-POC™ test provides an accurate and affordable option for RT-PCR at point-of-care without the need for sample pre-processing and laboratory handling. The Q-POC™ test would enable rapid diagnosis and clinical triage in acute care and other settings.

6.
EBioMedicine ; 72: 103629, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1469839

ABSTRACT

The COVID-19 pandemic caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) poses an unprecedented challenge to humanity. SARS-CoV-2 infections range from asymptomatic to severe courses of COVID-19 with acute respiratory distress syndrome (ARDS), multiorgan involvement and death. Risk factors for disease severity include older age, male sex, increased BMI and pre-existing comorbidities. Ethnicity is also relevant to COVID-19 susceptibility and severity. Host genetic predisposition to COVID-19 is now increasingly recognized and whole genome and candidate gene association studies regarding COVID-19 susceptibility have been performed. Several common and rare variants in genes related to inflammation or immune responses have been identified. We summarize research on COVID-19 host genetics and compile genetic variants associated with susceptibility to COVID-19 and disease severity. We discuss candidate genes that should be investigated further to understand such associations and provide insights relevant to pathogenesis, risk classification, therapy response, precision medicine, and drug repurposing.


Subject(s)
COVID-19/genetics , Genetic Predisposition to Disease , Immunity , COVID-19/enzymology , COVID-19/immunology , COVID-19/metabolism , Humans , Severity of Illness Index
7.
PLoS Negl Trop Dis ; 15(7): e0009551, 2021 07.
Article in English | MEDLINE | ID: covidwho-1301918

ABSTRACT

BACKGROUND: Individuals infected with SARS-CoV-2 develop neutralising antibodies. We investigated the proportion of individuals with SARS-CoV-2 neutralising antibodies after infection and how this proportion varies with selected covariates. METHODOLOGY/PRINCIPAL FINDINGS: This systematic review and meta-analysis examined the proportion of individuals with SARS-CoV-2 neutralising antibodies after infection and how these proportions vary with selected covariates. Three models using the maximum likelihood method assessed these proportions by study group, covariates and individually extracted data (protocol CRD42020208913). A total of 983 reports were identified and 27 were included. The pooled (95%CI) proportion of individuals with neutralising antibodies was 85.3% (83.5-86.9) using the titre cut off >1:20 and 83.9% (82.2-85.6), 70.2% (68.1-72.5) and 54.2% (52.0-56.5) with titres >1:40, >1:80 and >1:160, respectively. These proportions were higher among patients with severe COVID-19 (e.g., titres >1:80, 84.8% [80.0-89.2], >1:160, 74.4% [67.5-79.7]) than those with mild presentation (56.7% [49.9-62.9] and 44.1% [37.3-50.6], respectively) and lowest among asymptomatic infections (28.6% [17.9-39.2] and 10.0% [3.7-20.1], respectively). IgG and neutralising antibody levels correlated poorly. CONCLUSIONS/SIGNIFICANCE: 85% of individuals with proven SARS-CoV-2 infection had detectable neutralising antibodies. This proportion varied with disease severity, study setting, time since infection and the method used to measure antibodies.


Subject(s)
Antibodies, Neutralizing/blood , Antibodies, Viral/blood , COVID-19/immunology , SARS-CoV-2/immunology , Acute Disease , COVID-19/epidemiology , Convalescence , Humans , Prevalence
8.
Int J Infect Dis ; 106: 265-268, 2021 May.
Article in English | MEDLINE | ID: covidwho-1279605

ABSTRACT

INTRODUCTION: Use of hydroxychloroquine in patients with coronavirus disease 2019 (COVID-19) was widespread and uncontrolled until recently. Patients vulnerable to severe COVID-19 are at risk of hydroxychloroquine interactions with co-morbidities and co-medications contributing to detrimental, including fatal, adverse treatment effects. METHODS: A retrospective survey was undertaken of health conditions and co-medications of patients with COVID-19 who were pre-screened for enrolment in a randomized, double-blind, placebo-controlled hydroxychloroquine multi-centre trial. RESULTS: The survey involved 305 patients [median age 71 (interquartile range 59-81) years]. The majority of patients (n = 279, 92%) considered for inclusion in the clinical trial were not eligible, mainly due to safety concerns caused by health conditions or co-medications. The most common were QT-prolonging drugs (n = 188, 62%) and haematologic/haemato-oncologic diseases (n = 39, 13%) which prohibited the administration of hydroxychloroquine. In addition, 165 (54%) patients had health conditions and 167 (55%) patients were on co-medications that did not prohibit the use of hydroxychloroquine but had a risk of adverse interactions with hydroxychloroquine. The most common were diabetes (n = 86, 28%), renal insufficiency (n = 69, 23%) and heart failure (n = 58, 19%). CONCLUSION: The majority of hospitalized patients with COVID-19 had health conditions or took co-medications precluding safe treatment with hydroxychloroquine. Therefore, hydroxychloroquine should be administered with extreme caution in elderly patients with COVID-19, and only in clinical trials.


Subject(s)
COVID-19/drug therapy , Hydroxychloroquine/adverse effects , SARS-CoV-2 , Aged , Aged, 80 and over , Comorbidity , Contraindications, Drug , Drug Interactions , Female , Germany/epidemiology , Humans , Male , Middle Aged , Retrospective Studies
9.
Sci Rep ; 11(1): 7754, 2021 04 08.
Article in English | MEDLINE | ID: covidwho-1174700

ABSTRACT

Serological testing is emerging as a powerful tool to progress our understanding of COVID-19 exposure, transmission and immune response. Large-scale testing is limited by the need for in-person blood collection by staff trained in venepuncture, and the limited sensitivity of lateral flow tests. Capillary blood self-sampling and postage to laboratories for analysis could provide a reliable alternative. Two-hundred and nine matched venous and capillary blood samples were obtained from thirty nine participants and analysed using a COVID-19 IgG ELISA to detect antibodies against SARS-CoV-2. Thirty eight out of thirty nine participants were able to self-collect an adequate sample of capillary blood (≥ 50 µl). Using plasma from venous blood collected in lithium heparin as the reference standard, matched capillary blood samples, collected in lithium heparin-treated tubes and on filter paper as dried blood spots, achieved a Cohen's kappa coefficient of > 0.88 (near-perfect agreement, 95% CI 0.738-1.000). Storage of capillary blood at room temperature for up to 7 days post sampling did not affect concordance. Our results indicate that capillary blood self-sampling is a reliable and feasible alternative to venepuncture for serological assessment in COVID-19.


Subject(s)
Blood Specimen Collection/methods , COVID-19 Serological Testing/methods , COVID-19/diagnosis , SARS-CoV-2/isolation & purification , Adult , COVID-19/blood , Dried Blood Spot Testing/methods , Enzyme-Linked Immunosorbent Assay/methods , Female , Humans , Male , Middle Aged , Young Adult
12.
Am J Trop Med Hyg ; 104(3): 1041-1044, 2021 Jan 11.
Article in English | MEDLINE | ID: covidwho-1024748

ABSTRACT

Hypoxemia is readily detectable by assessing SpO2 levels, and these are important in optimizing COVID-19 patient management. Hyperlactatemia is a marker of tissue hypoxia, particularly in patients with increased oxygen requirement and microvascular obstruction. We monitored peripheral venous lactate concentrations in hospitalized patients with moderate to severe COVID-19 (n = 18) and in mild ambulatory COVID-19 patients in home quarantine (n = 16). Whole blood lactate decreased significantly during the clinical course and recovery in hospitalized patients (P = 0.008). The blood lactate levels were significantly higher in hospitalized patients than ambulatory patients (day 1: hospitalized versus ambulatory patients P = 0.002; day 28: hospitalized versus ambulatory patients P = < 0.0001). Elevated lactate levels may be helpful in risk stratification, and serial monitoring of lactate may prove useful in the care of hospitalized COVID-19 patients.


Subject(s)
Ambulatory Care Facilities/statistics & numerical data , COVID-19/physiopathology , Hospitalization/statistics & numerical data , Lactic Acid/blood , Adolescent , Adult , Biomarkers/blood , COVID-19/epidemiology , Comorbidity , Female , Germany/epidemiology , Humans , Hypoxia/blood , Longitudinal Studies , Male , Middle Aged , Severity of Illness Index , Treatment Outcome , Young Adult
13.
Emerg Infect Dis ; 27(1)2021 01.
Article in English | MEDLINE | ID: covidwho-951873

ABSTRACT

We investigated the dynamics of seroconversion in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. During March 29-May 22, 2020, we collected serum samples and associated clinical data from 177 persons in London, UK, who had SARS-CoV-2 infection. We measured IgG against SARS-CoV-2 and compared antibody levels with patient outcomes, demographic information, and laboratory characteristics. We found that 2.0%-8.5% of persons did not seroconvert 3-6 weeks after infection. Persons who seroconverted were older, were more likely to have concurrent conditions, and had higher levels of inflammatory markers. Non-White persons had higher antibody concentrations than those who identified as White; these concentrations did not decline during follow-up. Serologic assay results correlated with disease outcome, race, and other risk factors for severe SARS-CoV-2 infection. Serologic assays can be used in surveillance to clarify the duration and protective nature of humoral responses to SARS-CoV-2 infection.


Subject(s)
COVID-19/blood , COVID-19/immunology , Immunoglobulin G/blood , SARS-CoV-2 , Seroconversion , Adult , Aged , Antibodies, Viral/blood , COVID-19/physiopathology , Enzyme-Linked Immunosorbent Assay , Female , Humans , Male , Middle Aged , Reverse Transcriptase Polymerase Chain Reaction
14.
Trends Parasitol ; 37(1): 8-11, 2021 01.
Article in English | MEDLINE | ID: covidwho-872441

ABSTRACT

Artemisinin-based combination therapies (ACTs) have demonstrated in vitro inhibition of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Artemisinins have also shown anti-inflammatory effects, including inhibition of interleukin-6 (IL-6) that plays a key role in the development of severe coronavirus disease 2019 (COVID-19). There is now sufficient evidence for the effectiveness of ACTs, and in particular artesunate/pyronaridine, to support clinical studies for COVID-19 infections.


Subject(s)
Antimalarials/therapeutic use , COVID-19/drug therapy , Drug Repositioning , Antiviral Agents/therapeutic use , Artemisinins/pharmacology , Artesunate/therapeutic use , Cytokine Release Syndrome/drug therapy , Drug Combinations , Humans , Naphthyridines/therapeutic use , SARS-CoV-2/drug effects
16.
BMJ ; 370: m3379, 2020 09 04.
Article in English | MEDLINE | ID: covidwho-744846

ABSTRACT

UPDATES: This is the tenth version (ninth update) of the living guideline, replacing earlier versions, available as data supplements. New recommendations will be published as updates to this guideline. CLINICAL QUESTION: What is the role of drugs in the treatment of patients with covid-19? CONTEXT: The evidence base for therapeutics for covid-19 is evolving with numerous recently completed randomised controlled trials (RCTs). In this update the Guideline Development Group (GDG) developed new recommendations for patients with non-severe covid-19, concerning the use of nirmatrelvir/ritonavir (2 RCTs, 3100 participants) and remdesivir (5 RCTs, 2710 participants). We have also revised the structure of the guideline to accommodate for an increasing number of effective treatment options to choose between. NEW RECOMMENDATION: • Nirmatrelvir/ritonavir: a strong recommendation for its use in patients at highest risk of hospitalisation; and a conditional recommendation against its use in patients at low risk of hospitalisation. In the absence of trial data, no recommendation on nirmatrelvir/ritonavir was made in patients with severe or critical illness. • Remdesivir: a conditional recommendation for its use in patients at highest risk of hospitalisation. UNDERSTANDING THE NEW RECOMMENDATIONS: In patients with non-severe illness at highest risk of hospitalisation, the recommendations for treatment with nirmatrelvir/ritonavir and remdesivir reflect what the GDG considered to be important reductions in admission to hospital (moderate certainty) with little or no impact on mortality, mechanical ventilation, time to symptom resolution (low to very low certainty), and adverse effects leading to drug discontinuation (high certainty for nirmatrelvir/ritonavir, moderate certainty for remdesivir), though diarrhoea and altered taste were noted more often with nirmatrelvir/ritonavir. Several treatment alternatives are now available for patients with non-severe covid-19 at highest risk of hospitalisation. In the absence of direct comparisons in trials, indirect comparisons from the living network meta-analysis have been used to inform the use of one drug over another with a related mechanism of action. Choices will depend on availability of the drugs, routes of administration (only intravenous for remdesivir), duration of treatment, and time from onset of symptoms to starting treatment in the trials. The strong recommendation for nirmatrelvir/ritonavir reflects what the GDG considered to represent a superior choice over other treatment options for those with non-severe illness at highest risk; it may prevent more hospitalisations than the alternatives, has fewer harms than molnupiravir, and is easier to administer than intravenous options such as remdesivir and the monoclonal antibodies. For monoclonal antibodies, efficacy may depend on the given SARS-CoV-2 variant, with a less certain benefit seen with the omicron BA1-2 variant which is dominating in many regions. There are no clinical data on combination treatment, and currently the GDG advises against combining antivirals in the absence of supporting evidence. UPDATES TO PRIOR RECOMMENDATIONS: The conditional (weak) recommendation for remdesivir in patients with non-severe illness at highest risk of hospitalisation replaces a previous conditional recommendation against treatment with remdesivir in all patients with covid-19 regardless of disease severity. The recommendation for patients with severe or critical illness is being updated using new evidence. PRIOR RECOMMENDATIONS: • Recommended for patients with severe or critical covid-19­a strong recommendation for systemic corticosteroids; a strong recommendation for IL-6 receptor blockers (tocilizumab or sarilumab), in combination with corticosteroids; a strong recommendation for baricitinib as an alternative to IL-6 receptor blockers, in combination with corticosteroids; and a conditional recommendation for casirivimab-imdevimab, for those with seronegative status, (where rapid viral genotyping is available to confirm infection with a susceptible SARS-CoV-2 variant). • Recommended for patients with non-severe covid-19­conditional recommendations for those at highest risk of hospitalisation for molnupiravir; sotrovimab; and for casirivimab-imdevimab (where rapid viral genotyping is available to confirm infection with a susceptible SARS-CoV-2 variant). • Not recommended for patients with non-severe covid-19­a conditional recommendation against systemic corticosteroids; and a strong recommendation against convalescent plasma. • Not recommended for patients with severe or critical covid-19­a recommendation against convalescent plasma, except in the context of a clinical trial; and a conditional recommendation against ruxolitinib and tofacitinib. • Not recommended, regardless of covid-19 disease severity­a strong recommendation against hydroxychloroquine; a strong recommendation against lopinavir/ritonavir; and a recommendation against ivermectin, except in the context of a clinical trial. ABOUT THIS GUIDELINE: This living guideline from the World Health Organization (WHO) incorporates new recommendations on two drugs for covid-19 and updates existing recommendations. The GDG typically evaluates a therapy when WHO judges sufficient evidence is available to make a recommendation. While the GDG takes an individual patient perspective in making recommendations, it also considers resource implications, acceptability, feasibility, equity, and human rights. This guideline was developed according to standards and methods for trustworthy guidelines making use of an innovative process to achieve efficiency in dynamic updating of recommendations. The methods are aligned with the WHO Handbook for Guideline Development and according to a pre-approved protocol (planning proposal) by the Guideline Review Committee (GRC). A box at the end of the article outlines key methodological aspects of the guideline process. MAGIC Evidence Ecosystem Foundation provides methodological support, including the coordination of living systematic reviews with network meta-analyses to inform the recommendations. The full version of the guideline is available online in MAGICapp and in PDF, with a summary version here in The BMJ.


Subject(s)
Adrenal Cortex Hormones/therapeutic use , Betacoronavirus , Coronavirus Infections/drug therapy , Pneumonia, Viral/drug therapy , COVID-19 , Humans , Pandemics , SARS-CoV-2 , World Health Organization
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