SARS CoV-2 seroprevalence and diagnostic accuracy during a COVID-19 outbreak in a major penitentiary complex in Brazil, June to July 2020

PurposeThis study aims to estimate the overall SARS-CoV-2 seroprevalence and evaluate the accuracy of an antibody rapid test compared to a reference serological assay during a COVID-19 outbreak in a prison complex housing over 13,000 prisoners in Brasília.Design/methodology/approachThe authors obtained a randomized, stratified representative sample of each prison unit and conducted a repeated serosurvey among prisoners between June and July 2020, using a lateral-flow immunochromatographic assay (LFIA). Samples were also retested using a chemiluminescence enzyme immunoassay (CLIA) to compare SARS-CoV-2 seroprevalence and 21-days incidence, as well as to estimate the overall infection fatality rate (IFR) and determine the diagnostic accuracy of the LFIA test.FindingsThis study identified 485 eligible individuals and enrolled 460 participants. Baseline and 21-days follow-up seroprevalence were estimated at 52.0% (95% CI 44.9–59.0) and 56.7% (95% CI 48.2–65.3) with LFIA;and 80.7% (95% CI 74.1–87.3) and 81.1% (95% CI 74.4–87.8) with CLIA, with an overall IFR of 0.02%. There were 78.2% (95% CI 66.7–89.7) symptomatic individuals among the positive cases. Sensitivity and specificity of LFIA were estimated at 43.4% and 83.3% for IgM;46.5% and 91.5% for IgG;and 59.1% and 77.3% for combined tests.Originality/valueThe authors found high seroprevalence of anti-SARS-CoV-2 antibodies within the prison complex. The occurrence of asymptomatic infection highlights the importance of periodic mass testing in addition to case-finding of symptomatic individuals;however, the field performance of LFIA tests should be validated. This study recommends that vaccination strategies consider the inclusion of prisoners and prison staff in priority groups.

Humoral Response to 3rd Dose Sars-Cov-2 Vaccine in Patients with Idiopathic Inflammatory Myopathies

Background. Vaccine-induced SARS-CoV-2 antibody responses are reduced in patients taking lymphocyte-depleting therapies, which are commonly prescribed for patients with idiopathic inflammatory myopathies (IIM). While a third vaccine dose (D3) augments the SARS-CoV-2 anti-spike response in some patients, there is a paucity of data on the humoral response following D3 in patients with IIM. Furthermore, the durability of antibody response is unknown. In this study, we evaluated serial antibody response for three months following a 3rd dose SARS-CoV-2 vaccination in IIM patients. Methods. Adults with a patient-reported diagnosis of idiopathic inflammatory myopathy who completed three-dose SARS-CoV-2 vaccination (two-dose BNT162b2 or mRNA-1273 followed by single mRNA or adenoviral vector dose) were recruited via social media campaign. Demographics and clinical characteristics were collected via patient report. Informed consent was provided electronically. Serial antibody responses were evaluated by the Roche Elecsys anti-SARS-CoV-2 S enzyme immunoassay, which measures total antibody to the SARS-CoV-2 S-receptor binding domain (RBD) protein (range 0. 4-2500U/ mL;positive >0.8U/mL). Poor antibody response was defined as anti-RBD titer <500U/mL based on predicted correlates of protective plasma neutralizing capacity. Those with prior COVID-19 infection were excluded. Associations were evaluated using Fisher's exact and Wilcoxon rank-sum tests as appropriate. Results. We evaluated serial anti-RBD titers in 59 participants (Table I). Most (93%) were female with median (IQR) age of 51 (41-62) years. Mycophenolate mofetil was the most frequently prescribed medication (45.6%). Participants completed primary vaccination with two-dose BNT162b2(54%) or mRNA-1273(46%). Median pre-D3 anti-RBD titer (IQR) was 65.8U/mL (4.6,473) at 158 (136-183) days following primary vaccination. Dose 3 included BNT162b2(47%), mRNA-1273(47%) or Ad.26.COV2.S (6%). Most (89.9%) received homologous D3 vaccination. 39% of participants reported holding peri-D3 immunosuppression with mycophenolate mofetil being the most commonly held medication in the peri-D3 period. Repeat anti-RBD testing was performed at a median (IQR) 30 (28-32) days post-D3. A higher antibody titer was seen in 89.9% participants following D3 with median (IQR) titer of 2500 U/mL (92,2500). Thirty-seven percent remained <500U/mL following D3;a greater proportion of these participants reported use of rituximab and greater number of immunosuppressive therapies compared to those with anti-RBD >=500U (72.7% versus 5.4%, p<0.001;3 therapies versus 2 therapies, p=0.03). Furthermore, 13.5% (8/59) remained below the threshold of positivity following D3;7/8 reported use of rituximab, 5/8 mycophenolate mofetil, or combination of these agents (4/8). There was not a significant difference in antibody titers among recipients of homologous/heterologous vaccination (p=0.22). Dose 3 was well tolerated with only 2 (3.4%) participants reporting disease flare requiring treatment within one month of vaccination;neither required intravenous therapy or hospital admission. Thirty-four (57.6%) participants underwent repeat anti-RBD testing three months following D3 with median (IQR) 2500U/mL (456,2500);73.53% (25/34) remained above threshold of >=500U/mL. Limitations of this study include small sample size and absence of healthy control group. Diagnosis was based on participant report and we did not routinely collect information on disease activity. Conclusion. We observed an augmented humoral response in most IIM patients following 3rd dose SARS-CoV-2 vaccination;antibody response was durable at three months. Dose 3 was well tolerated. Over 1/3 participants failed to develop adequate response following D3, namely those on rituximab therapy and on higher number of immunosuppressive therapies. These patients should be prioritized for prophylactic therapies to enhance protection against COVID-19 infection.

Sensitivity of SARS-CoV-2 antibody tests with late convalescent sera.

SARS-CoV-2-specific IgM antibodies wane during the first three months after infection and IgG antibody levels decline. This may limit the ability of antibody tests to identify previous SARS-CoV-2 infection at later time points. To examine if the diagnostic sensitivity of antibody tests falls off, we compared the sensitivity of two nucleoprotein-based antibody tests, the Roche Elecsis II Anti-SARS-CoV-2 and the Abbott SARS-CoV-2 IgG assay and three glycoprotein-based tests, the Abbott SARS-CoV-2 IgG II Quant, Siemens Atellica IM COV2T and Euroimmun SARS-CoV-2 assay with 53 sera obtained 6 months after SARS-CoV-2 infection. The sensitivity of the Roche, Abbott SARS-CoV-2 IgG II Quant and Siemens antibody assays was 94.3% (95% confidence interval (CI) 84.3-98.8%), 98.1 % (95% CI: 89.9-100%) and 100 % (95% CI: 93.3-100%). The sensitivity of the N-based Abbott SARS-CoV-2 IgG and the glycoprotein-based Euroimmun ELISA was 45.3 % (95% CI: 31.6-59.6%) and 83.3% (95% CI: 70.2-91.9%). The nucleoprotein-based Roche and the glycoprotein-based Abbott receptor binding domain (RBD) and Siemens tests were more sensitive than the N-based Abbott and the Euroimmun antibody tests (p = 0.0001 to p = 0.039). The N-based Abbott antibody test was less sensitive 6 months than 4-10 weeks after SARS-CoV-2 infection (p = 0.0001). The findings show that most SARS-CoV-2 antibody assays correctly identified previous infection 6 months after infection. The sensitivity of pan-Ig antibody tests was not reduced at 6 months when IgM antibodies have usually disappeared. However, one of the nucleoprotein-based antibody tests significantly lost diagnostic sensitivity over time.

Factors affecting the sensitivity of quantitative severe acute respiratory syndrome coronavirus 2 antigen test.

INTRODUCTION: The accuracy of nucleic acid amplification tests (NAATs) is affected by various factors; however, studies examining the factors affecting the accuracy of quantitative severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigen test (QAT) are limited. METHODS: A total of 347 nasopharyngeal samples were collected from patients with coronavirus disease 2019 (COVID-19), and the date of onset was obtained from the electronic medical records. The SARS-CoV-2 antigen level was measured using Lumipulse Presto SARS-CoV-2 Ag (Presto), while NAAT was performed using the Ampdirect 2019-nCoV Detection Kit. RESULTS: Presto had a sensitivity rate of 95.1% (95% confidence interval: 92.8-97.4) in detecting the SARS-CoV-2 antigen in 347 samples. The number of days from symptom onset to sample collection was negatively correlated with the amount of antigen (r = -0.515) and sensitivity of Presto (r = -0.711). The patients' age was lower in the Presto-negative samples (median age, 39 years) compared with that in the Presto-positive samples (median age, 53 years; p < 0.01). A significant positive correlation was observed between age (excluding teenagers) and Presto sensitivity (r = 0.764). Meanwhile, no association was found between the mutant strain, sex, and Presto results. CONCLUSION: Presto is useful for the accurate diagnosis of COVID-19 owing to its high sensitivity when the number of days from symptom onset to sample collection is within 12 days. Furthermore, age may affect the results of Presto, and this tool has a relatively low sensitivity in younger patients.

Assessment of specific T-cell immunity in patients who have been ill and vaccinated against COVID-19.

Introduction. In the context of a pandemic of a new coronavirus infection (COVID-19), research on the peculiarities of the formation of an immune response to SARS-CoV-2 in patients who have been ill and vaccinated is of particular relevance. However, most studies are currently devoted to evaluating only the humoral link of immunity, and its cellular component remains insufficiently studied. The aim of the study was to evaluate the features of the formation and changes of the T-cell link of immunity in patients with a new coronavirus infection and vaccinated against this disease. Materials and methods. The study was performed on the basis of the clinical and diagnostic laboratory of the European Medical Center "UMMC-Health "LLC. Specific T-cell immunity was evaluated using ELISPOT technology. In the course of the study, 72 blood samples of employees of medical organizations were analyzed, including 26 from those who had a new coronavirus infection, 23 from persons who were intact according to COVID-19 before vaccination and 23 from the same employees after vaccination (<<Gam-Covid-Vac>>). In addition, each of the study participants was examined to determine specific class G antibodies (IgG) by solid-phase enzyme immunoassay using SARS-CoV-2-IgG-ELISA-BEST test systems (manufactured by VECTOR-BEST JSC). Results and discussion. In the group of patients (26 people), T-lymphocytes capable of specifically reacting to SARSCoV-2 antigens were detected in 100% of cases, even in individuals with IgG elimination. It should be noted that the response was more pronounced when meeting with M-and N-pepdids, compared with S-protein. 22 out of 23 COVID-19 intact individuals had no T-cell immunity to coronavirus infection before vaccination, but one employee had a response to 3 proteins-M, N, S, which indicates that he had previously encountered the SARS-CoV-2 virus. After vaccination with the drug "Gam-Covid-Vac", 22 (95.6%) employees revealed a T-cell response, while 21-only to S-protein, and an employee with a previously detected immune response-after vaccination, the response to M -, N-proteins remained almost at the same level, and the cellular response to S-peptide doubled. Conclusion. Thus, based on the results of the study, important materials were obtained on the peculiarities of the formation of a specific T-cell immune response to a new coronavirus infection. The obtained data provide a broader understanding of the immune response in new coronavirus infection in patients who have been ill and vaccinated and can be used in the future when planning preventive and anti-epidemic measures.Copyright © 2022 Interregional public organization Association of infectious disease specialists of Saint-Petersburg and Leningrad region (IPO AIDSSPbR). All rights reserved.

Prognostic value of initial KL-6 (Krebs von den Lungen 6) plasma level during COVID-19 pneumonia

Introduction: Krebs von den Lungen-6(KL-6) is useful in the diagnosis and severity assessment of diffuse interstitial lung disease. The objective of our study was to determine the prognostic value of the initial KL-6 plasma level in COVID-19 pneumonia Methods: All patients hospitalized between March 2020 and May 2020 for a suspected COVID-19 pneumonia in our Chest department of university hospital (Paris, France) were included. Initial referred as within 72 h of diagnostic suspicion, KL-6 plasma concentration in U/mL was measured by a ChemiLuminescent Enzyme Immunoassay (LUMIPULSE, Japan). Survival analyses were performed using a Cox regression and modeled by a Kaplan-Meier curve Results: 66 COVID-19 patients with initial KL-6 plasma measurement were analyzed, among whom 47 were men and average age was 64+/-14 yrs. Median KL-6 plasma concentration was 409+/-312 U/mL. KL-6 was significantly higher in men (p=0.003), elders (p=0.0001) and for higher Charlson's score (p=0.002). Higher KL-6 concentration was significantly associated with in-hospital mortality (HR: 8.66;95% CI:1.1-69.2), radiological extension of lesions on chest CT-scan (p=0.0040), higher WHO severity score (p=0.042), but not with admission in intensive care unit. In the 9 (14%) non surviving COVID-19 patients, KL-6 plasma concentration increased while it remained stable or decreased in survivors. At 3 months (n=48), DLCO was negatively correlated with the initial KL-6 value (r = -0.47, p=0.001) Conclusion(s): Initial KL-6 plasma concentration is associated with in-hospital mortality, unfavorable outcome, and persistent impairment of DLCO at 3 months. Initial KL-6 plasma determination appears as a prognostic biomarker in COVID-19 pneumonia.

SARS-CoV-2 Omicron detection by antigen tests using saliva.

The Omicron emerged in November 2021 and became the predominant SARS-CoV-2 variant globally. It spreads more rapidly than ancestral lineages and its rapid detection is critical for the prevention of disease outbreaks. Antigen tests such as immunochromatographic assay (ICA) and chemiluminescent enzyme immunoassay (CLEIA) yield results more quickly than standard polymerase chain reaction (PCR). However, their utility for the detection of the Omicron variant remains unclear. We herein evaluated the performance of ICA and CLEIA in saliva from 51 patients with Omicron and 60 PCR negative individuals. The sensitivity and specificity of CLEIA were 98.0% (95%CI: 89.6-100.0%) and 100.0% (95%CI: 94.0-100.0%), respectively, with fine correlation with cycle threshold (Ct) values. The sensitivity and specificity of ICA were 58.8% (95%CI: 44.2-72.4%) and 100.0% (95%CI: 94.0-100.0%), respectively. The sensitivity of ICA was 100.0% (95%CI: 80.5-100.0%) when PCR Ct was less than 25. The Omicron can be efficiently detected in saliva by CLEIA. ICA also detects high viral load Omicron using saliva.

A Laboratory-Based Study on Multiple Biomarker Testing in the Diagnosis of COVID-19-Associated Pulmonary Aspergillosis (CAPA): Real-Life Data.

(1) Background: Coronavirus disease 2019 (COVID-19)-associated pulmonary aspergillosis (CAPA) raises concerns to contribute to an increased mortality. The incidence of CAPA varies widely within hospitals and countries, partly because of difficulties in obtaining a reliable diagnosis. (2) Methods: Here, we assessed Aspergillus culture-positive and culture-negative respiratory tract specimens via direct fungal microscopy (gold standard) and compared the results with galactomannan enzyme immunoassay (GM-EIA) and Aspergillus PCR. (3) Results: 241 respiratory samples from patients suffering from SARS-CoV-2 pneumonia were evaluated. Results showed both diagnostic tools, Aspergillus PCR and GM-EIA, to be positive or negative displaying a sensitivity of 0.90, a specificity of 0.77, a negative predictive value (NPV) of 0.95, and a positive predictive value (PPV) of 0.58 in Aspergillus sp. culture and microscopic-positive specimens. Non-bronchoalveolar lavage (BAL) samples, obtained within a few days from the same patient, showed a high frequency of intermittent positive or negative GM-EIA or Aspergillus PCR results. Positivity of a single biomarker is insufficient for a proper diagnosis. A broad spectrum of Aspergillus species was detected. (4) Conclusions: Our study highlights the challenges of combined biomarker testing as part of diagnosing CAPA. From the results presented, we highly recommend the additional performance of direct microscopy in respiratory specimens to avoid overestimation of fungal infections by applying biomarkers.

Humoral and cellular immunogenicity against SARS-CoV- 2 mRNA vaccine in patients with inflammatory rheumatic disease, Comparison of mRNA-1273 vaccine and BNT162b2

Objectives: To assess humoral and cellular immune responses and safety profiles after two doses of different mRNA vaccine against SARS-CoV- 2;BNT162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna) in patients with rheumatic musculoskeletal disease (RMD). Method(s): We enrolled consecutive, previously uninfected RMD patients with inflammatory rheumatic diseases receiving mRNA vaccine including BNT162b2 and mRNA-1273. Healthy participants all receiving BNT162b2 were recruited as control. Blood samples were obtained 3weeks after second dose of vaccines. We measured titres of neutralizing antibodies against SARS-CoV- 2 with chemiluminescent enzyme immunoassay to evaluate humoral responses and assessed T-cell immunity responses with interferon releasing assay against SARS-CoV- 2 in a part of the patients. Adverse reaction symptoms were obtained from participants through questionnaire. Result(s): A total of 1040 RMD patients and healthy 621 control participants were enrolled. Among RMD patients with immunosuppressants, 704 were received BNT162b2 and 156 were received mRNA-1273. Neutralizing antibody titres 3 weeks after vaccination and positive seroconversion rates were significantly higher in healthy participants with BNT162b2 and RMD patients with mRNA-1273 compared with RMD patients with BNT162b2;neutralizing antibody titre, 23.9 +/- 14.2 IU/mL vs 29.4 +/- 33.9 IU/mL vs 10.8 +/- 16.5 IU/mL, p < 0.001;seroconversion rates, 99.5% vs 99.4% vs 80.2%, p < 0.001, respectively, We identified that age, glucocorticoid (prednisolone dose > 7.5mg/day), and use of immunosuppressants including methotrexate, mycophenolate and rituximab, are associated with attenuation of humoral responses in patients with BNT162b2. T cell reaction against SARS-CoV- 2 were also higher in patients with RMD vaccinated with mRNA-1273 than those with BNT162b2 (Interferon gamma levels for antigen 1, 3.2 +/- 6.5 IU/mL vs 0.6 +/- 1.3 IU/mL, p = 0.002;for antigen 2, 3.2 +/- 6.3 IU/mL vs 1.0 +/- 2.1 IU/mL, p = 0.021, respectively). Regarding adverse reaction of mRNA vaccine, the proportion of systemic adverse reactions including fever and general fatigue are significantly higher in healthy controls and RMD patients with mRNA-1273 than those with BNT162b2;fever, 46.2% vs 56.7% vs 14.3%, p < 0.001;general fatigue, 62.6% vs 73.0% vs 38.5%, p < 0.001, respectively, while the frequency of background RMD flare after vaccination were not significantly different between mRNA-1273 and BNT162b2 (5.2% [n = 8] vs. 3.7% [n = 26], p = 0.41) Conclusion(s): We demonstrated higher humoral, cellular immunogenicity of the SARS-CoV- 2 mRNA-1273 (Moderna) compared with the BNT162b2 (Pfizer-BioNTech) in RMD patients. Although reactogenicity including systemic adverse reaction including fever and fatigue were observed mRNA1273 vaccinated patients, proportion of RMD relapse were similar between the patients with mRNA-1273 and BNT162b2.

Dynamics of fecal zonulin levels in COVID-19 and in the post-covid period in children

Fecal zonulin is currently used as a biomarker of intestinal permeability. Objective. To assess the state of intestinal permeability in a novel coronavirus infection (COVID-19) in children based on the determination of fecal zonulin levels. Patients and methods. Fecal zonulin levels were assessed in 35 children with COVID-19, which was mild in most of them. Fecal sampling was performed at the time of diagnosis and 14 days after the start of observation. Patients were then randomized into two groups. Group 1 (study, n = 19) received Maxilac Baby synbiotic (2 sachets once a day) for 1 month, group 2 (control, n = 16) did not receive any probiotics, prebiotics, and adsorbents for a month;the third stool sampling was performed 1 month after the second. The study was carried out by enzyme immunoassay using the IDK Zonulin ELISA test system (Immundiagnostik AG, Germany). Results. Fecal zonulin levels were 77.38 +/- 12.59 ng/mL at the beginning of the disease, 76.26 +/- 13.10 ng/mL on day 14, and 82.64 +/- 11.99 ng/mL after one month (p1-2 = 0.75;p1-3 = 0.04;p2-3 = 0.04). Children who received Maxilac Baby for a month did not have significant increases in zonulin levels (76.26 +/- 13.10 ng/mL and 79.02 +/- 11.87 ng/mL;p = 0.40), while the control group demonstrated significantly elevated zonulin levels (76.26 +/- 13.10 ng/mL and 87.95 +/- 10.96 ng/mL;p = 0.048). Conclusion. A month after the coronavirus infection, the intestinal permeability in children increases significantly, whereas it does not change during the course of the disease. Administration of Maxilac Baby synbiotic in children who had a mild-to-moderate coronavirus infection and did not receive antibiotics effectively prevents intestinal permeability disorders in them. Copyright © 2022, Dynasty Publishing House. All rights reserved.

Characteristics of Olokizumab Pharmacokinetics in Patients with Novel Coronavirus Infection Covid-19

The aim of the article is to study pharmacokinetic characteristics of intravenous olokizumab in patients with moderate COVID-19 to relieve a hyperinflammation syndrome. Materials and methods. The pharmacokinetic study was conducted as a part of a phase III clinical study (RESET, NCT05187793) on the efficacy and safety of a new olokizumab regimen (intravenous, at the doses of 128 mg or 256 mg) in COVID-19 patients. Plasma concentrations of olokizumab were determined by the enzyme immunoassay. The population analysis was performed using a previously developed pharmacokinetic model based on a linear two compartment. Results. The pharmacokinetic analysis included the data from 8 moderate COVID-19 patients who had been administrated with olokizumab intravenously at the dose of 128 mg. According to the analysis results in this population, there was an increase in the drug clearance, compared with the data obtained in healthy volunteers and the patients with rheumatoid arthritis: 0.435, 0.178 and 0.147 l/day, respectively. The parameters analysis within the framework of a population pharmacokinetic model showed that the main factors for the increased olokizumab clearance are a high body mass index. In addition, the presence of COVID-19 itself is an independent factor in increasing the drug clearance. Conclusion. After the intravenous olokizumab administration, an increase in the drug clearance is observed in moderate COVID-19 patients against the background of the disease course. The main contribution to the increased clearance is made by the characteristics of the population of COVID-19 patients associated with the risk of a severe disease and inflammation. When administered intravenously at the dose of 128 mg, a therapeutically significant olokizumab level was maintained throughout the acute disease phase for 28 days. Copyright © 2022 Volgograd State Medical University, Pyatigorsk Medical and Pharmaceutical Institute. All rights reserved.

Bacterial ligands in the rehabilitation of healthcare workers after COVID-19

Immune defense mechanisms in survivors of the COronaVIrus Disease-19 (COVID-19) and development of their rehabilitation during the pandemic both portray a great scientific and practical interest. The aim of the study was to explore effect of Immunovac-VP-4 (I-VP-4), a vaccine based on bacterial ligands, on the clinical and airway mucosal immunity parameters, along with systemic immune response in a group of medical workers in post-COVID period and in persons who did not develop the disease. Methods. 82 healthcare workers aged from 18 to 65 years were included in a prospective open controlled study. The participants were divided into 4 groups: groups 1 (n = 20) and 2 (n = 27) included those with a history of COVID-19, and groups 3 (n = 18) and 4 (n = 17) included those who did not have the disease. Volunteers in groups 1 and 3 received I-VP-4. Samples of oral fluid, induced sputum, nasopharyngeal and oropharyngeal mucosa scrapings, and venous blood were examined. The levels of total secretory immunoglobulin class A (sIgA) and immunoglobulin G (IgG) were determined by enzyme immunoassay. The phagocytic index (PI) of leukocytes was assessed by flow cytometry. Results. The group of patients who did not have COVID-19 and received IVP-4 (Group 3) showed a tendency to a smaller number of COVID-19 cases, as well as some reduction in days of incapacity for work due to the acute respiratory infections (ARI). The vaccine improved airway mucosal immunity parameters and innate immune response. sIgA increased in the induced sputum (p < 0.005) and unchanged in the oropharyngeal mucosa samples in Group 1. The PI of macrophages in oral fluid doubled (p < 0.05) in this group. At the same time, those parameters decreased in Group 2. In non-infected vaccinated patients (Group 3), a significant increase of PI of blood monocytes was found on the day 90 of the study (p < 0.05). Also, a four-fold increase of PI of macrophages in oral fluid in comparison with Group 4 (p < 0.05) was noted. Conclusion. I-VP-4 improved airway mucosal immunity mechanisms and the systemic immune response. The vaccine can be recommended for rehabilitation programs for COVID-19 survivors and for prevention of ARIs. Copyright © 2022 Medical Education. All rights reserved.

Lenzilumab Treatment in COVID-19 Pneumonia Reduces Circulating Cytokines and Markers of Systemic Inflammation

Background. Coronavirus disease 2019 (COVID-19) results from SARS-CoV-2-induced hyperinflammatory immune response, orchestrated by granulocyte-macrophage colony-stimulating factor (GM-CSF). GM-CSF increases interleukin-6 (IL-6) levels, ultimately leading to increased C-reactive protein (CRP). The LIVE-AIR trial demonstrated that lenzilumab, the GM-CSF neutralizing antibody, improved the likelihood of survival without invasive mechanical ventilation (IMV) in hospitalized COVID-19 patients requiring supplemental oxygen but not IMV. This sub-analysis correlated levels of cytokines before and after lenzilumab treatment. Methods. LIVE-AIR was a phase 3, randomized, double-blind, placebocontrolled trial (NCT04351152). Patients hospitalized with COVID-19 pneumonia, requiring only supplemental oxygen, were randomized to receive lenzilumab (1800 mg in three equally divided doses of 600 mg, q8h) or placebo IV infusion, in addition to standard of care which included remdesivir and corticosteroids. Blood taken at baseline (BL) and subsequent to treatment through day 10 (D10) were obtained and analyzed by high sensitivity enzyme immunoassay for GM-CSF, IL-6, and CRP. Results. Baseline IL-6 levels (Loge-transformed for all cytokines and biomarkers) were linearly correlated with higher baseline GM-CSF levels (slope=0.60, p< 0.001). Baseline CRP levels were linearly correlated with higher baseline IL-6 levels (slope=0.29, p < 0.001). GM-CSF levels decreased with lenzilumab treatment on day 1 (D1) which persisted through D10 (Table). In contrast, GM-CSF increased with placebo treatment. IL-6 levels decreased only with lenzilumab treatment. CRP following lenzilumab or placebo treatment decreased on D1 to similar levels and further decreased on D10 only with lenzilumab treatment. Cytokine Levels Associated with Lenzilumab Treatment Conclusion. Lenzilumab decreased GM-CSF as well as downstream cytokines and systemic biomarkers of inflammation during the hyperinflammatory immune response of COVD-19.

Use cases for rapid antigen-detecting tests for COVID-19 screening and surveillance: a systematic review

Background. Testing remains critical to controlling the COVID-19 pandemic. Antigen-detecting rapid diagnostic tests (Ag-RDTs), which can be used at the point of care, have the potential to increase access to COVID-19 testing, particularly in settings with limited laboratory capacity. This systematic review synthesized literature on specific use cases and performance of Ag-RDTs for detecting SARS-CoV-2, for the first comprehensive assessment of Ag-RDT use in real-world settings. Methods. We searched three databases (PubMed, EMBASE and medRxiv) up to 12 April 2021 for publications on Ag-RDT use for large-scale screening and surveillance of COVID-19, excluding studies of only presumptive COVID-19 patients. We tabulated data on the study setting, populations, type of test, diagnostic performance, and operational findings. We assessed risk of bias using QUADAS-2 and an adapted tool for prevalence studies. Results. From 4313 citations, 39 studies conducted in asymptomatic and symptomatic individuals were included. Of 39 studies, 37 (94.9%) investigated lateral flow Ag-RDTs and 2 (5.1%) investigated multiplex sandwich chemiluminescent enzyme immunoassay Ag-RDTs. Six categories of testing initiatives were identified: mass screening (n=13), targeted screening (n=11), healthcare entry testing (n=6), at-home testing (n=4), surveillance (n=4) and prevalence survey (n=1). Sensitivity and specificity values by testing category are shown in the table. Ag-RDTs were noted as convenient, easy-to-use, and low cost, with a rapid turnaround time and high user acceptability. Risk of bias was generally low or unclear across studies. Conclusion. During the first year of the COVID-19 pandemic, Ag-RDTs were used across a wide range of real-world settings for screening and surveillance of COVID-19 in both symptomatic and asymptomatic individuals. Ag-RDTs were fast and simple to run, but due to their often low sensitivity, careful consideration must be given to their implementation and interpretation. Ag-RDTs have subsequently been rolled out more broadly and recommended for COVID-19 self-testing.

Vaccine-Induced Immune Thrombotic Thrombocytopenia (Vitt) by a Third Dose of Chadox1 Ncov-19 (Astrazeneca) after Bnt162b2 (Pfizer-Biontech)

An atypical case of VITT was described resulting from a vaccination schedule where the third booster with ChAdOx1 nCoV-19 (AstraZeneca) was administered. The patient received a complete vaccination schedule with two doses of Pfizer-BioNTech (BNT162b2) without any complications before the third dose. However, the patient has developed an infrequent yet extreme prothrombotic;hypercoagulable state caused by platelet-activating anti-Platelet Factor 4 (PF4) antibodies. This phenomenon is typically triggered by the proximate administration of an adenoviral vector vaccine against COVID-19. The patient's symptoms began ten days after taking the third dose of the ChAdOx1 nCoV-19 vaccine (AstraZeneca). His main complaints when hospitalized were severe headaches and right abdominal pain. The blood tests and MRI scan imaging findings were very characteristic of VITT, and a rare cerebral venous sinus thrombosis was found. Also, a markedly elevated D-dimer and strong positive PF4-dependent enzyme-immunoassay test results were documented. Due to discerning clinical suspicion, this patient was rapidly treated with immunoglobulin infusion for two days and oral steroids for three days. Subsequently, he was anticoagulated with the new oral anticoagulant edoxaban after platelet numbers recovery. In a few days, platelets normalized, and D-dimer levels decreased, while anti- PF4-dependent enzyme-immunoassay test results showed a slow decline. He was discharged taking oral edoxaban without any sequeal. Copyright © 2022

Serological effect of mRNA vaccination against COVID-19 in multiple sclerosis patients treated with immunosuppressive DMTs

Background: Immunosuppressive therapies may impact immune response to COVID-19 vaccines in persons with multiple sclerosis (pwMS). Accordingly, effects of vaccination in pwMS treated with disease-modifying therapies (DMTs) need further elucidation. Aim(s): To investigate COVID-19 BNT162b2 vaccine effect concerning antibody seroconversion, T cells-associated cytokines production and immunophenotype assessment in pwMS under three different DMTs: cladribine, fingolimod, ocrelizumab. Method(s): Enzyme immunoassay test was used for anti-spike IgG detection in 98 DMTs-treated pwMS completing first vaccination cycle. In a subset of patients (n=47), serum T cells-associated cytokines (GrB, IFN-gamma and TNF-alpha) were quantified using an automatic ELISA (ELLA) and blood immunophenotype was assessed by flow cytometry. ANCOVA followed by post hoc tukey's test was used to compare anti-spike IgG response in the different DMTs, Student's paired t-test was used to evaluate differences between pre- and post-vaccination in pairwise samples and Pearson's correlation was applied to evaluate association between spike-specific IgG antibody titer and lymphocytes count. Result(s): More pwMS treated with ocrelizumab (63%) lacked anti-spike IgG compared to patients treated with cladribine (14%) and fingolimod (20%) (p<0.001). When present, the anti-spike IgG titer in the ocrelizumab group was lower than in cladribine- (p<0.001) and in fingolimod-treated pwMS (p=0.003). No significant differences in lymphocytes count and T-cell associated cytokines were observed in cladribine- and in fingolimod-treated pwMS, while in pwMS on ocrelizumab a significant increase in GrB serum levels (p=0.021) and a trend of increased CD4+ T cells count were observed after vaccination. Specifically considering non-seroconverted ocrelizumab-treated pwMS, a significant increase of GrB serum levels (p=0.008) and of CD4+ T lymphocytes count (p=0.040) was foundafter vaccination and a negative correlation was observed between anti-spike IgG production and CD4+T cells count (rho=-0.452, p=0.014). Conclusion(s): Our data confirmed differences in spike-specific antibodies among different DMTs and provided evidence of T-cell immunity preservation and activations after BNT162b2 vaccination in ocrelizumab-treated pwMS, specifically in pwMS patients lacking anti-spike IgG, suggesting a protective T-cell response that might explain why the ongoing treatment with ocrelizumab is not associated with a higher risk of COVID-19 infection.

Functional studies on the interaction between anti-PF4 antibodies and anticoagulants in vaccine-induced thrombotic thrombocytopenia

Background: With increasing number of vaccinations against SARS-CoV-2, rare but life threatening thrombotic events at unusual sites have been reported, and collectively this phenomenon is termed as vaccine-induced immune thrombotic thrombocytopenia (VITT). Pathophysiology of VITT is similar to that of heparin-induced thrombocytopenia (HIT), and associated with platelet-activating antibodies against platelet factor 4 (PF4). Aim(s): Current guidelines for anticoagulation in VITT patients are issued accordingly, with a focus on non-heparin anticoagulants. In this study, we investigated the interactions of heparin, danaparoid, fondaparinux and argatroban with VITT-Ab/ PF4 complexes. Method(s): We utilized an in-house enzyme immunoassays (EIA) to estimate antibody binding, inhibition and dissociation of preformed PF4-VITT complexes. Using biolayer interferometry (BLI), we analyzed binding kinetics and dissociation of complexes in real time. In a flow-based ex vivo model, we assessed the impact of anticoagulants on VITT-mediated thrombus formation. Result(s): We found that heparin and danaparoid not only inhibited VITT IgG binding to PF4 but were also able to effectively dissociate preformed PF4/IgG complexes in EIA. In BLI, binding of PF4 specific antibodies was observed for all VITT samples tested, and we found remarkable changes in their dissociation after addition of various anticoagulants. Furthermore, IgGs from VITT patients induce increased thrombus formation in comparison to the healthy controls (mean % SAC +/- SEM: 11.59 +/- 0.57 vs. 1.99 +/- 0.34 respectively, p < 0.001), which can further be effectively inhibited with danaparoid and heparin (mean % SAC +/- SEM 2.82 +/- 0.50 and 1.85 +/- 0.56. p < 0.001). Fondaparinux and argatroban inhibited thrombus formation;however, they did not affect antibody binding. Conclusion(s): Taken together, our data shed a light on suitability of anticoagulants in VITT, and indicate that negatively charged anticoagulants can disrupt VITT-Ab/ PF4 interactions, which might serve as an approach to reduce antibody-mediated complications in VITT. Our results should be confirmed, however, in a clinical setting before a recommendation regarding the selection of anticoagulation in VITT patients could be made.

Humoral and cell-mediated responses to BNT162b2 mRNA vaccine against SARS-CoV-2 in people with cystic fibrosis

Background: The BNT162b2 mRNAvaccine (Pfizer-BioNTech) was the first anti-SARS-CoV-2 vaccine approved and has shown 95% efficacy against severe COVID-19. The vaccine elicits a combined humoral and cellular adaptive immune response, albeit with high between-subject variability. The humoral response wanes 4 to 6 months after vaccination and, considered alone, does not appear to be indicative of protective immune memory. The role of cell-mediated immune response, which may be more relevant in the long-term protection against SARS-CoV-2, has not been clarified. Our aim was to evaluate the humoral and cell-mediated immune responses induced by administration of the BNT162b2 vaccine 6 to 8 months after the second dose in people with cystic fibrosis (PwCF) and the possible relationship between the anti-SARS-CoV-2 immunoglobulin (Ig)G-S antibodies (Spike protein) titer and the CD4+/CD8+ cell-mediated response. Method(s): One hundred thirteen PwCF (43 male, median age 21, range 11- 64) were enrolled, including 12 patients with virologically confirmed prior SARS-CoV-2 infection. Patients receiving chronic steroid therapy and transplant recipients were excluded. Serum IgG-S was determined by Elecsys anti-SARS-CoV-2 S (Roche) enzyme immunoassay with cut-off for positive response at 0.8 U/mL;cell-mediated immune response was measured using the STANDARDTM F CoviFERON FIA (interferon-gamma) system, a newrapid interferon gamma release assay (IGRA),with cut-off for positive response at 0.30 U/mL on standard F2400 (SD Biosensor, Inc. Korea). Result(s): All patients showed a humoral response 6 to 8 months after the second vaccine dose, with a median antibody titer of 1,288 U/mL (interquartile range [IQR] 610-2397). PwCF who were previously infected by SARS-CoV-2 had higher antibody titers than those naive to the virus (median 6,302, IQR 4272-8349 vs 1,180, IQR 535-1742;p < 0.001). Sixtyone patients (54%) developed a cell-mediated immune response against SARS-CoV-2. Antibody titer was higher in patients with a positive cellmediated response (median 1453, IQR 778-4473) than in those without (median 1054, IQR 510-1498) ( p = 0.01). Conclusion(s): All patients developed an adequate humoral response after two doses of BNT162b2 vaccine;the antibody titer was higher in patients with previous SARS-CoV-2 infection than in naive patients. We documented a cell-mediated response in 54% of patients, and this was associated with a higher antibody titer. Further studies are needed to understand whether development of cell-mediated immune response is elicited with greater protection against severe COVID-19 in PwCF. If this were the case, this rapid and relatively inexpensive test might be a useful tool to determine the best timing for additional vaccine doses in this clinically vulnerable population. Copyright © 2022, European Cystic Fibrosis Society. All rights reserved

Neutralising Antibodies in Healthcare Workers after Two Doses of Covishield Vaccine at Three Months and Six Months: A Single-centre Observational Study

Introduction: The emergence of Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2) as a pandemic has put the global population at risk for its infection. It has also led to an accelerated effort to develop vaccines that can mitigate progression to severe infections at a minimum. The ambiguity about existence of antibodies in the human serum poses problem in formulating public health policies like suitable interval between doses of vaccines, appropriate time for vaccinating population, post natural infection, necessity of booster doses along with single dose. Aim: To estimate neutralising antibody level following vaccination of Healthcare Workers (HCWs) after three months and six months respectively. Materials and Methods: This was a prospective observational study performed in Sri Jayadeva Institute of Cardiovascular Sciences and Research, Bengaluru, Karnataka, India after Institutional Ethics Committee (IEC) approval from January 2021 to February 2022. The study was conducted in 304 HCWs in the institute who had received two doses of Recombinant ChAdOx1 nCoV- 19 Corona Virus Vaccine (Covishield). 41 HCWs who were naturally infected with SARS-CoV-2 either before or after vaccination were also included. These participants were then subjected to IgG neutralising antibody titer estimation at three months and six months, postvaccination. Results: The study included 304 eligible HCWs. Majority of the participants belonged to the age group of 31-40 years (35.9%). Majority of the study participants were females (51%). Of the 304 participants, 263 were uninfected and 41 participants had been infected before and after vaccination. At the six month follow-up, it was observed that all but one HCW had seroconverted with majority of the participants showing more than 60% antibody level. Participants in the age group of 31-40 years showed the highest level and this observation was found to be statistically significant. Conclusion: Neutralising antibody response in HCWs is a key indicator of the efficacy of the vaccination program for Coronavirus Disease-2019 (COVID-19) in India.

Sars-CoV-2 Antibody Response Before and After Third Dose of Homologous mRNA Vaccine in Liver Transplant Recipients

Purpose: Liver transplant (LT) recipients have a decreased response to 2 doses of SARS-CoV-2 vaccine compared to the general population, so we aimed to understand response to a third dose to inform vaccination strategies. Method(s): LT recipients in our observational cohort who received 3 homologous mRNA vaccines and available antibody levels pre- and post-dose 3 (D3) were identified. Those who reported a prior COVID-19 diagnosis or used belatacept were excluded. The peak anti-spike antibody level collected between the second (D2) and third dose (D3), was compared to the antibody level at 1 month post-D3. Samples were tested with Roche Elecsys Anti-Sars-CoV-2 enzyme immunoassay (EIA) (positive >=0.8 U/mL) or EUROIMMUN EIA (positive >=1.1 AU). Result(s): 146 participants completed 3 homologous doses of BNT162b2 (53%) or mRNA-1273 (47%) vaccines between 5/15/2021 - 11/8/2021. The median (IQR) time of peak pre-D3 antibody collection was 89 (31, 104) days post-D2. The median time of 1-month post-D3 antibody collection was 30 (23, 33) days. The median time between D2 and D3 was 168 (149-188) days. Overall, 125/146 (86%) were seropositive pre-D3, and 139/146 (95%) were seropositive post-D3 (Figure 1). There were no seroreversions post D3, and among the 21 seronegative recipients pre-D3, 14 (67%) seroconverted post-D3. Risk factors significantly associated with persistent seronegativity post-D3 were less time since LT (1.3 vs 6 years, p=0.042), mycophenolate use (100% vs 37%, p=0.001), BNT162b2 series (100% vs 50%, p=0.01), and pre-D3 seronegative status (86% vs 10%, p<0.001). Conclusion(s): Most LT recipients have excellent responses to a third homologous mRNA vaccine dose, greater than that seen in other transplant recipients. Persons seronegative after D2, however, show weaker response and may remain at high risk for SARS-CoV-2 infection despite D3.