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1.
Sci Rep ; 11(1): 24448, 2021 12 27.
Article in English | MEDLINE | ID: covidwho-1585777

ABSTRACT

COVID-19 mRNA vaccines are highly effective at preventing COVID-19. Prior studies have found detectable SARS-CoV-2 IgG antibodies in oral mucosal specimens of participants with history of COVID-19. To assess the development of oral SARS-CoV-2 IgG antibodies among people who received either the Moderna or Pfizer/BioNTech COVID-19 vaccination series, we developed a novel SARS-CoV-2 IgG enzyme-linked immunosorbent assay (ELISA) to quantify the concentrations of oral and nasal mucosal SARS-CoV-2 IgG levels. We enrolled 52 participants who received the Moderna vaccine and 80 participants who received the Pfizer/BioNTech vaccine. Oral mucosal specimens were self-collected by participants prior to or on the day of vaccination, and on days 5, 10, 15, and 20 following each vaccination dose and 30, 60, and 90 days following the second vaccination dose. A subset of the cohort provided additional nasal mucosal specimens at every time point. All participants developed detectable oral mucosal SARS-CoV-2 IgG antibodies by 15 days after the first vaccination dose. There were no significant differences in oral mucosal antibody concentrations once participants were fully vaccinated in the Moderna and Pfizer/BioNTech vaccines. Oral or nasal mucosal antibody testing could be an inexpensive and less invasive alternative to serum antibody testing. Further research is needed to understand the duration of detectable oral or nasal mucosal antibodies and how antibody concentrations change with time.


Subject(s)
Antibodies, Viral/analysis , Immunoglobulin G/analysis , Mouth Mucosa/metabolism , Respiratory System/metabolism , /immunology , Adult , Aged , COVID-19/prevention & control , COVID-19/virology , Female , Health Personnel , Humans , Male , Middle Aged , SARS-CoV-2/immunology , SARS-CoV-2/isolation & purification , Time Factors , Vaccination , Young Adult , /administration & dosage
2.
Biomedica ; 41(Sp. 2): 86-102, 2021 10 15.
Article in English, Spanish | MEDLINE | ID: covidwho-1529016

ABSTRACT

INTRODUCTION: Immunological markers have been described during COVID-19 and persist after recovery. These immune markers are associated with clinical features among SARSCoV-2 infected individuals. Nevertheless, studies reporting a comprehensive analysis of the immune changes occurring during SARS-CoV-2 infection are still limited. OBJECTIVE: To evaluate the production of proinflammatory cytokines, the antibody response, and the phenotype and function of NK cells and T cells in a Colombian family cluster with SARS-CoV-2 infection. MATERIALS AND METHODS: Proinflammatory cytokines were evaluated by RT-PCR and ELISA. The frequency, phenotype, and function of NK cells (cocultures with K562 cells) and T-cells (stimulated with spike/RdRp peptides) were assessed by flow cytometry. Anti-SARS-CoV-2 antibodies were determined using indirect immunofluorescence and plaque reduction neutralization assay. RESULTS: During COVID-19, we observed a high proinflammatory-cytokine production and a reduced CD56bright-NK cell and cytotoxic response. Compared with healthy controls, infected individuals had a higher frequency of dysfunctional CD8+ T cells CD38+HLA-DR-. During the acute phase, CD8+ T cells stimulated with viral peptides exhibited a monofunctional response characterized by high IL-10 production. However, during recovery, we observed a bifunctional response characterized by the co-expression of CD107a and granzyme B or perforin. CONCLUSION: Although the proinflammatory response is a hallmark of SARS-CoV-2 infection, other phenotypic and functional alterations in NK cells and CD8+ T cells could be associated with the outcome of COVID-19. However, additional studies are required to understand these alterations and to guide future immunotherapy strategies.


Introducción. Se han descrito diferentes marcadores inmunológicos durante la COVID-19, los cuales persisten incluso después de la convalecencia y se asocian con los estadios clínicos de la infección. Sin embargo, aún son pocos los estudios orientados al análisis exhaustivo de las alteraciones del sistema inmunológico en el curso de la infección. Objetivo. Evaluar la producción de citocinas proinflamatorias, la reacción de anticuerpos, y el fenotipo y la función de las células NK y los linfocitos T en una familia colombiana con infección por SARS-CoV-2. Materiales y métodos. Se evaluaron las citocinas proinflamatorias mediante RT-PCR y ELISA; la frecuencia, el fenotipo y la función de las células NK (en cocultivos con células K562) y linfocitos T CD8+ (estimulados con péptidos spike/RdRp) mediante citometría de flujo, y los anticuerpos anti-SARS-CoV-2, mediante inmunofluorescencia indirecta y prueba de neutralización por reducción de placa. Resultados. Durante la COVID-19 hubo una producción elevada de citocinas proinflamatorias, con disminución de las células NK CD56bright y reacción citotóxica. Comparados con los controles sanos, los individuos infectados presentaron con gran frecuencia linfocitos T CD8+ disfuncionales CD38+HLA-DR-. Además, en los linfocitos T CD8+ estimulados con péptidos virales, predominó una reacción monofuncional con gran producción de IL-10 durante la fase aguda y una reacción bifuncional caracterizada por la coexpresión de CD107a y granzima B o perforina durante la convalecencia. Conclusión. Aunque la reacción inflamatoria caracteriza la infección por SARS-CoV-2, hay otras alteraciones fenotípicas y funcionales en células NK y linfocitos T CD8+ que podrían asociarse con la progresión de la infección. Se requieren estudios adicionales para entender estas alteraciones y guiar futuras estrategias de inmunoterapia.


Subject(s)
COVID-19/immunology , Killer Cells, Natural , SARS-CoV-2/immunology , T-Lymphocytes , Adult , Antibodies, Viral/analysis , CD56 Antigen/immunology , Case-Control Studies , Colombia , Family Health , Granzymes/metabolism , Humans , Interleukin-10/metabolism , Interleukin-1beta/blood , Interleukin-6/blood , Interleukin-8/blood , K562 Cells , Killer Cells, Natural/cytology , Killer Cells, Natural/immunology , Lymphocyte Activation , Male , Middle Aged , Perforin/metabolism , Phenotype , Receptors, CCR7/metabolism , T-Lymphocytes/cytology , T-Lymphocytes/immunology , Tumor Necrosis Factor-alpha/blood , Young Adult
5.
Front Immunol ; 12: 744887, 2021.
Article in English | MEDLINE | ID: covidwho-1497079

ABSTRACT

Background: Although the serological antibody responses induced by SARS-CoV-2 vaccines are well characterized, little is known about their ability to elicit mucosal immunity. Objectives: This study aims to examine and compare the mucosal and systemic responses of recipients of two different vaccination platforms: mRNA (Comirnaty) and inactivated virus (CoronaVac). Methods: Serial blood and nasal epithelial lining fluid (NELF) samples were collected from the recipients of either Comirnaty or CoronaVac. The plasma and NELF immunoglobulins A and G (IgA and IgG) specific to SARS-CoV-2 S1 protein (S1) and their neutralization effects were quantified. Results: Comirnaty induced nasal S1-specific immunoglobulin responses, which were evident as early as 14 ± 2 days after the first dose. In 64% of the subjects, the neutralizing effects of NELF persisted for at least 50 days. Moreover, 85% of Comirnaty recipients exhibited S1-specific IgA and IgG responses in plasma by 14 ± 2 days after the first dose. By 7 ± 2 days after the booster, all plasma samples possessed S1-specific IgA and IgG responses and were neutralizing. The induction of S1-specific plasma antibodies by CoronaVac was IgG dominant, and 83% of the subjects possessed S1-specific IgG by 7 ± 2 days after the booster, with neutralizing effects. Conclusion: Comirnaty induces S1-specific IgA and IgG responses with neutralizing activity in the nasal mucosa; a similar response is not seen with CoronaVac. Clinical Implication: The presence of a nasal response with mRNA vaccine may provide additional protection compared with inactivated virus vaccine. However, whether such widespread immunological response may produce inadvertent adverse effects in other tissues warrants further investigation.


Subject(s)
COVID-19 Vaccines/immunology , Immunity, Mucosal , SARS-CoV-2/immunology , Adult , Age Factors , Aged , Antibodies, Neutralizing/analysis , Antibodies, Viral/analysis , COVID-19/immunology , COVID-19/prevention & control , Female , Humans , Immunoglobulin A/analysis , Immunoglobulin G/analysis , Male , Middle Aged , Nasal Mucosa/immunology , Spike Glycoprotein, Coronavirus/immunology , Vaccination , Vaccines, Inactivated/immunology , Vaccines, Synthetic/immunology , Young Adult
6.
Eur J Immunol ; 51(11): 2665-2676, 2021 11.
Article in English | MEDLINE | ID: covidwho-1482126

ABSTRACT

To monitor infection by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and successful vaccination against coronavirus disease 2019 (COVID-19), the kinetics of neutralizing or blocking anti-SARS-CoV-2 antibody titers need to be assessed. Here, we report the development of a quick and inexpensive surrogate SARS-CoV-2 blocking assay (SUBA) using immobilized recombinant human angiotensin-converting enzyme 2 (hACE2) and human cells expressing the native form of surface SARS-CoV-2 spike protein. Spike protein-expressing cells bound to hACE2 in the absence or presence of blocking antibodies were quantified by measuring the optical density of cell-associated crystal violet in a spectrophotometer. The advantages are that SUBA is a fast and inexpensive assay, which does not require biosafety level 2- or 3-approved laboratories. Most importantly, SUBA detects blocking antibodies against the native trimeric cell-bound SARS-CoV-2 spike protein and can be rapidly adjusted to quickly pre-screen already approved therapeutic antibodies or sera from vaccinated individuals for their ACE2 blocking activities against any emerging SARS-CoV-2 variants.


Subject(s)
Antibodies, Blocking/blood , Antibodies, Neutralizing/blood , Antibodies, Viral/analysis , COVID-19 Serological Testing/methods , COVID-19/diagnosis , Flow Cytometry/methods , Antibodies, Blocking/immunology , Antibodies, Neutralizing/immunology , COVID-19/immunology , Humans , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/immunology
8.
Nat Commun ; 12(1): 5621, 2021 09 23.
Article in English | MEDLINE | ID: covidwho-1437680

ABSTRACT

Although serological studies have shown that antibodies against SARS-CoV-2 play an important role in protection against (re)infection, the dynamics of mucosal antibodies during primary infection and their potential impact on viral load and the resolution of disease symptoms remain unclear. During the first pandemic wave, we assessed the longitudinal nasal antibody response in index cases with mild COVID-19 and their household contacts. Nasal and serum antibody responses were analysed for up to nine months. Higher nasal receptor binding domain and spike protein-specific antibody levels at study inclusion were associated with lower viral load. Older age was correlated with more frequent COVID-19 related symptoms. Receptor binding domain and spike protein-specific mucosal antibodies were associated with the resolution of systemic, but not respiratory symptoms. Finally, receptor binding domain and spike protein-specific mucosal antibodies remained elevated up to nine months after symptom onset.


Subject(s)
Antibodies, Neutralizing/analysis , Antibodies, Viral/analysis , COVID-19/diagnosis , Nasal Mucosa/metabolism , SARS-CoV-2/immunology , Adolescent , Adult , Antibodies, Neutralizing/immunology , Antibodies, Neutralizing/metabolism , Antibodies, Viral/immunology , Antibodies, Viral/metabolism , COVID-19/blood , COVID-19/immunology , COVID-19/virology , COVID-19 Serological Testing/statistics & numerical data , Child , Humans , Immunity, Mucosal , Longitudinal Studies , Male , Middle Aged , Nasal Mucosa/immunology , Nasal Mucosa/virology , Severity of Illness Index , Viral Load , Young Adult
9.
Front Immunol ; 12: 701411, 2021.
Article in English | MEDLINE | ID: covidwho-1430694

ABSTRACT

In March 2020, the World Health Organization (WHO) declared a global health emergency-the coronavirus disease 2019 (COVID-19) pandemic. Since then, the development and implementation of vaccines against the virus amidst emerging cases of re-infection has prompted researchers to work towards understanding how immunity develops and is sustained. Serological testing has been instrumental in monitoring the development and persistence of antibodies against SARS-CoV-2 infection, however inconsistencies in detection have been reported by different methods. As serological testing becomes more commonplace, it is important to establish widespread and repeatable processes for monitoring vaccine efficacy. Therefore, we present enzyme linked immunosorbent assays (ELISAs) compatible for antibody detection in saliva as highly accurate, efficacious, and scalable tools for studying the immune response in individuals vaccinated against SARS-CoV-2.


Subject(s)
Antibodies, Neutralizing/analysis , Antibodies, Viral/analysis , COVID-19/immunology , SARS-CoV-2/immunology , Saliva/immunology , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19 Vaccines/immunology , Enzyme-Linked Immunosorbent Assay , Humans
10.
Sci Rep ; 11(1): 18428, 2021 09 16.
Article in English | MEDLINE | ID: covidwho-1415954

ABSTRACT

Here we describe a homogeneous bioluminescent immunoassay based on the interaction between Fc-tagged SARS-CoV-2 Spike RBD and human ACE2, and its detection by secondary antibodies labeled with NanoLuc luciferase fragments LgBit and SmBit. The assay utility for the discovery of novel inhibitors was demonstrated with a panel of anti-RBD antibodies, ACE2-derived miniproteins and soluble ACE2. Studying the effect of RBD mutations on ACE2 binding showed that the N501Y mutation increased RBD apparent affinity toward ACE2 tenfold that resulted in escaping inhibition by some anti-RBD antibodies. In contrast, while E484K mutation did not highly change the binding affinity, it still escaped antibody inhibition likely due to changes in the epitope recognized by the antibody. Also, neutralizing antibodies (NAbs) from COVID-19 positive samples from two distinct regions (USA and Brazil) were successfully detected and the results further suggest the persistence of NAbs for at least 6 months post symptom onset. Finally, sera from vaccinated individuals were tested for NAbs and showed varying neutralizing activity after first and second doses, suggesting the assay can be used to assess immunity of vaccinated populations. Our results demonstrate the broad utility and ease of use of this methodology both for drug discovery and clinical research applications.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , Antibodies, Neutralizing/analysis , COVID-19/prevention & control , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/metabolism , Antibodies, Viral/analysis , Brazil , COVID-19/immunology , Humans , Luciferases/genetics , Luciferases/metabolism , Luminescent Measurements , Mutation , Protein Binding , Protein Domains , SARS-CoV-2/immunology , SARS-CoV-2/isolation & purification , Spike Glycoprotein, Coronavirus/genetics , United States , Vaccination
11.
Sci Rep ; 11(1): 18313, 2021 09 15.
Article in English | MEDLINE | ID: covidwho-1412108

ABSTRACT

In the context of the coronavirus disease 2019 (COVID-19) pandemic there has been an increase of the use of antigen-detection rapid diagnostic tests (Ag-RDT). The performance of Ag-RDT vary greatly between manufacturers and evaluating their analytical limit of detection (LOD) has become high priority. Here we describe a manufacturer-independent evaluation of the LOD of 19 marketed Ag-RDT using live SARS-CoV-2 spiked in different matrices: direct culture supernatant, a dry swab, and a swab in Amies. Additionally, the LOD using dry swab was investigated after 7 days' storage at - 80 °C of the SARS-CoV-2 serial dilutions. An LOD of ≈ 5.0 × 102 pfu/ml (1.0 × 106 genome copies/ml) in culture media is defined as acceptable by the World Health Organization. Fourteen of 19 Ag-RDTs (ActiveXpress, Espline, Excalibur, Innova, Joysbio, Mologic, NowCheck, Orient, PanBio, RespiStrip, Roche, Standard-F, Standard-Q and Sure-Status) exceeded this performance criteria using direct culture supernatant applied to the Ag-RDT. Six Ag-RDT were not compatible with Amies media and a decreased sensitivity of 2 to 20-fold was observed for eleven tests on the stored dilutions at - 80 °C for 7 days. Here, we provide analytical sensitivity data to guide appropriate test and sample type selection for use and for future Ag-RDT evaluations.


Subject(s)
Antigens, Viral/immunology , COVID-19 Serological Testing/methods , COVID-19/diagnosis , SARS-CoV-2/immunology , Animals , Antibodies, Viral/analysis , Chlorocebus aethiops , Humans , Limit of Detection , Reagent Kits, Diagnostic , Specimen Handling , Vero Cells
12.
N Engl J Med ; 385(19): 1761-1773, 2021 11 04.
Article in English | MEDLINE | ID: covidwho-1410390

ABSTRACT

BACKGROUND: BNT162b2 is a lipid nanoparticle-formulated, nucleoside-modified RNA vaccine encoding a prefusion-stabilized, membrane-anchored severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) full-length spike protein. BNT162b2 is highly efficacious against coronavirus disease 2019 (Covid-19) and is currently approved, conditionally approved, or authorized for emergency use worldwide. At the time of initial authorization, data beyond 2 months after vaccination were unavailable. METHODS: In an ongoing, placebo-controlled, observer-blinded, multinational, pivotal efficacy trial, we randomly assigned 44,165 participants 16 years of age or older and 2264 participants 12 to 15 years of age to receive two 30-µg doses, at 21 days apart, of BNT162b2 or placebo. The trial end points were vaccine efficacy against laboratory-confirmed Covid-19 and safety, which were both evaluated through 6 months after vaccination. RESULTS: BNT162b2 continued to be safe and have an acceptable adverse-event profile. Few participants had adverse events leading to withdrawal from the trial. Vaccine efficacy against Covid-19 was 91.3% (95% confidence interval [CI], 89.0 to 93.2) through 6 months of follow-up among the participants without evidence of previous SARS-CoV-2 infection who could be evaluated. There was a gradual decline in vaccine efficacy. Vaccine efficacy of 86 to 100% was seen across countries and in populations with diverse ages, sexes, race or ethnic groups, and risk factors for Covid-19 among participants without evidence of previous infection with SARS-CoV-2. Vaccine efficacy against severe disease was 96.7% (95% CI, 80.3 to 99.9). In South Africa, where the SARS-CoV-2 variant of concern B.1.351 (or beta) was predominant, a vaccine efficacy of 100% (95% CI, 53.5 to 100) was observed. CONCLUSIONS: Through 6 months of follow-up and despite a gradual decline in vaccine efficacy, BNT162b2 had a favorable safety profile and was highly efficacious in preventing Covid-19. (Funded by BioNTech and Pfizer; ClinicalTrials.gov number, NCT04368728.).


Subject(s)
COVID-19 Vaccines , COVID-19/prevention & control , Immunogenicity, Vaccine , Adolescent , Adult , Aged , Aged, 80 and over , Antibodies, Viral/analysis , COVID-19/epidemiology , COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/immunology , Child , Female , Follow-Up Studies , Humans , Immunization, Secondary , Incidence , Male , Middle Aged , SARS-CoV-2/immunology , Single-Blind Method , Treatment Outcome , Young Adult
13.
Microbiol Spectr ; 9(2): e0069321, 2021 10 31.
Article in English | MEDLINE | ID: covidwho-1410323

ABSTRACT

Noninvasive salivary antibody immunoassays can enable low-cost epidemiological surveillance of infections. This study involved developing and validating a multiplex suspension immunoassay on the Luminex platform to measure immunoglobulin G (IgG) responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid and spike (S) proteins, and the spike protein's S1 and S2 subunits and receptor binding domain. Multiple versions of these recombinant proteins acquired from commercial and noncommercial sources were evaluated. Assay development and validation utilized saliva and serum samples from coronavirus disease 2019 (COVID-19) cases procured from commercial sources and negative controls from a prepandemic survey. Saliva was also collected in a demonstration survey by mail involving adult individuals in the United States who were diagnosed with SARS-CoV-2 infection 15 to 80 days prior to sample collection. The survey had an 83% valid sample return rate (192 samples from 38 states). Most COVID-19 cases (93%) reported mildly symptomatic or asymptomatic infections. The final salivary assay based on the best-performing spike and nucleocapsid proteins had a sensitivity of 87.1% (95% bootstrap confidence interval, 82.1 to 91.7%) and specificity of 98.5% (95.0 to 100%) using 227 and 285 saliva samples, respectively. The same assay had 95.9% (92.8 to 98.9%) sensitivity and 100% (98.4 to 100%) specificity in serum (174 and 285 serum samples, respectively). Salivary and serum antibody responses to spike and nucleocapsid proteins were strongly correlated in 22 paired samples (r = 0.88 and r = 0.80, respectively). Antibody responses peaked at approximately 50 days postonset; greater illness severity was associated with stronger responses. This study demonstrated that a salivary antibody assay can be used in large-scale population surveys by mail to better characterize public health impacts of COVID-19. IMPORTANCE Given the enormous impacts of the COVID-19 pandemic, developing tools for population surveillance of infection is of paramount importance. This article describes the development of a multiplex immunoassay on a Luminex platform to measure salivary immunoglobulin G responses to the spike protein, its two subunits and receptor binding domain, and the nucleocapsid protein of SARS-CoV-2. The assay validation utilized serum and saliva samples from prepandemic controls and recent COVID-19 cases. A survey by mail targeting recent COVID-19 cases across the United States also demonstrated the utility of safe, at-home self-collection of saliva. By incorporating multiple SARS-CoV-2 proteins, this assay may differentiate responses to natural SARS-CoV-2 infections from responses to most vaccines. Application of this noninvasive immunoassay in COVID-19 surveillance can help provide estimates of cumulative incidence rates of symptomatic and asymptomatic infections in various communities and subpopulations, temporal patterns of antibody responses, and risk factors for infection.


Subject(s)
Antibodies, Viral/analysis , COVID-19 Serological Testing/methods , COVID-19/diagnosis , Immunoglobulin G/analysis , SARS-CoV-2/immunology , Saliva/immunology , Adolescent , Adult , Aged , Coronavirus Nucleocapsid Proteins/immunology , Female , Humans , Male , Middle Aged , Phosphoproteins/immunology , Postal Service , Sensitivity and Specificity , Spike Glycoprotein, Coronavirus/immunology , Young Adult
15.
Clin Microbiol Infect ; 27(9): 1212-1220, 2021 Sep.
Article in English | MEDLINE | ID: covidwho-1392213

ABSTRACT

BACKGROUND: Pool-testing strategies combine samples from multiple people and test them as a group. A pool-testing approach may shorten the screening time and increase the test rate during times of limited test availability and inadequate reporting speed. Pool testing has been effectively used for a wide variety of infectious disease screening settings. Historically, it originated from serological testing in syphilis. During the current coronavirus disease 2019 (COVID-19) pandemic, pool testing is considered across the globe to inform opening strategies and to monitor infection rates after the implementation of interventions. AIMS: This narrative review aims to provide a comprehensive overview of the global efforts to implement pool testing, specifically for COVID-19 screening. SOURCES: Data were retrieved from a detailed search for peer-reviewed articles and preprint reports using Medline/PubMed, medRxiv, Web of Science, and Google up to 21st March 2021, using search terms "pool testing", "viral", "serum", "SARS-CoV-2" and "COVID-19". CONTENT: This review summarizes the history and theory of pool testing. We identified numerous peer-reviewed articles that describe specific details and practical implementation of pool testing. Successful examples as well as limitations of pool testing, in general and specifically related to the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA and antibodies, are reviewed. While promising, significant operational, pre-analytical, logistical, and economic challenges need to be overcome to advance pool testing. IMPLICATIONS: The theory of pool testing is well understood and numerous successful examples from the past are available. Operationalization of pool testing requires sophisticated processes that can be adapted to the local medical circumstances. Special attention needs to be paid to sample collection, sample pooling, and strategies to avoid re-sampling.


Subject(s)
COVID-19 Testing/methods , COVID-19/diagnosis , SARS-CoV-2/isolation & purification , Specimen Handling/methods , Antibodies, Viral/analysis , Diagnostic Tests, Routine , Humans , Mass Screening , RNA, Viral/genetics , Research Design , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Sensitivity and Specificity
16.
Kidney Int ; 99(6): 1470-1477, 2021 06.
Article in English | MEDLINE | ID: covidwho-1386157

ABSTRACT

Patients with end stage kidney disease receiving in-center hemodialysis (ICHD) have had high rates of SARS-CoV-2 infection. Following infection, patients receiving ICHD frequently develop circulating antibodies to SARS-CoV-2, even with asymptomatic infection. Here, we investigated the durability and functionality of the immune responses to SARS-CoV-2 infection in patients receiving ICHD. Three hundred and fifty-six such patients were longitudinally screened for SARS-CoV-2 antibodies and underwent routine PCR-testing for symptomatic and asymptomatic infection. Patients were regularly screened for nucleocapsid protein (anti-NP) and receptor binding domain (anti-RBD) antibodies, and those who became seronegative at six months were screened for SARS-CoV-2 specific T-cell responses. One hundred and twenty-nine (36.2%) patients had detectable antibody to anti-NP at time zero, of whom 127 also had detectable anti-RBD. Significantly, at six months, 71/111 (64.0%) and 99/116 (85.3%) remained anti-NP and anti-RBD seropositive, respectively. For patients who retained antibody, both anti-NP and anti-RBD levels were reduced significantly after six months. Eleven patients who were anti-NP seropositive at time zero, had no detectable antibody at six months; of whom eight were found to have SARS-CoV-2 antigen specific T cell responses. Independent of antibody status at six months, patients with baseline positive SARS-CoV-2 serology were significantly less likely to have PCR confirmed infection over the following six months. Thus, patients receiving ICHD mount durable immune responses six months post SARS-CoV-2 infection, with fewer than 3% of patients showing no evidence of humoral or cellular immunity.


Subject(s)
Antibodies, Viral/analysis , COVID-19/immunology , Kidney Failure, Chronic/therapy , Renal Dialysis/adverse effects , SARS-CoV-2/immunology , COVID-19 Testing , Female , Humans , Immunity , Male , Pandemics , Polymerase Chain Reaction , Reinfection , SARS-CoV-2/isolation & purification , Serologic Tests/methods
17.
Sci Rep ; 11(1): 3081, 2021 02 04.
Article in English | MEDLINE | ID: covidwho-1387463

ABSTRACT

Clinic-based estimates of SARS-CoV-2 may considerably underestimate the total number of infections. Access to testing in the US has been heterogeneous and symptoms vary widely in infected persons. Public health surveillance efforts and metrics are therefore hampered by underreporting. We set out to provide a minimally biased estimate of SARS-CoV-2 seroprevalence among adults for a large and diverse county (Orange County, CA, population 3.2 million). We implemented a surveillance study that minimizes response bias by recruiting adults to answer a survey without knowledge of later being offered SARS-CoV-2 test. Several methodologies were used to retrieve a population-representative sample. Participants (n = 2979) visited one of 11 drive-thru test sites from July 10th to August 16th, 2020 (or received an in-home visit) to provide a finger pin-prick sample. We applied a robust SARS-CoV-2 Antigen Microarray technology, which has superior measurement validity relative to FDA-approved tests. Participants include a broad age, gender, racial/ethnic, and income representation. Adjusted seroprevalence of SARS-CoV-2 infection was 11.5% (95% CI: 10.5-12.4%). Formal bias analyses produced similar results. Prevalence was elevated among Hispanics (vs. other non-Hispanic: prevalence ratio [PR] = 1.47, 95% CI 1.22-1.78) and household income < $50,000 (vs. > $100,000: PR = 1.42, 95% CI: 1.14 to 1.79). Results from a diverse population using a highly specific and sensitive microarray indicate a SARS-CoV-2 seroprevalence of ~ 12 percent. This population-based seroprevalence is seven-fold greater than that using official County statistics. In this region, SARS-CoV-2 also disproportionately affects Hispanic and low-income adults.


Subject(s)
Antibodies, Viral/analysis , COVID-19 , /statistics & numerical data , Adolescent , Adult , Bias , COVID-19/diagnosis , COVID-19/epidemiology , California/epidemiology , Female , Humans , Immunoglobulin G/analysis , Immunoglobulin M/analysis , Male , Middle Aged , Prevalence , Public Health Surveillance , Seroepidemiologic Studies , Young Adult
19.
Int J Environ Res Public Health ; 17(23)2020 12 04.
Article in English | MEDLINE | ID: covidwho-1389354

ABSTRACT

BACKGROUND: This study aimed to characterize sources of knowledge on the means of prevention of SARS-CoV-2 infections as well as to assess the methods of preventing SARS-CoV-2 infection among police employees in Poland and their potential impact on the risk of SARS-CoV-2 infection. METHODS: The study consisted of two phases: questionnaire and laboratory tests for SARS-CoV-2 infection. The questionnaire included 30 questions related to risk factors, knowledge about SARS-CoV-2, and methods of infection prevention. RESULTS: Data were obtained from 5082 police employees. The most common source of knowledge for a daily update on SARS-CoV-2 infection prevention was the Internet (42.6%), television (40.3%), and radio (39.7%). The most commonly used methods of SARS-CoV-2 infection included washing one's hands for at least 20 seconds (95.8%), wearing facemasks (82.9%), and physical distancing (74.9%). Results of IgG tests were lower in police units where the overall compliance with the preventive measures was higher (p < 0.01). Women were more likely to exercise SARS-CoV-2 infection prevention behaviors compared to men. Compliance with the recommended protective measures increased with age. CONCLUSIONS: Lower anti-SARS-CoV-2 IgG seropositivity rates were observed in police units with better overall compliance with the preventive measures, suggesting the key importance of group rather than individual behaviors.


Subject(s)
COVID-19/prevention & control , Health Behavior , Health Policy , Police , Adult , Antibodies, Viral/analysis , Communicable Disease Control , Female , Humans , Immunoglobulin G/analysis , Male , Middle Aged , Pandemics , Poland/epidemiology , Surveys and Questionnaires , Young Adult
20.
Sci Rep ; 11(1): 17325, 2021 08 30.
Article in English | MEDLINE | ID: covidwho-1379337

ABSTRACT

Two-dose messenger RNA vaccines against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are highly effective in preventing symptomatic COVID-19 infection. However, the durability of protection is not known, nor is the effectiveness against emerging viral variants. Additionally, vaccine responses may differ based on prior SARS-CoV-2 exposure history. To investigate protection against SARS-CoV-2 variants we measured binding and neutralizing antibody responses following both vaccine doses. We document significant declines in antibody levels three months post-vaccination, and reduced neutralization of emerging variants, highlighting the need to identify correlates of clinical protection to inform the timing of and indications for booster vaccination.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , Antibodies, Neutralizing/analysis , COVID-19/prevention & control , SARS-CoV-2/immunology , Vaccines, Synthetic/administration & dosage , Adult , Antibodies, Neutralizing/metabolism , Antibodies, Viral/analysis , Antibodies, Viral/metabolism , COVID-19/immunology , COVID-19/metabolism , COVID-19 Nucleic Acid Testing , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/immunology , Female , Humans , Immunoglobulin G/analysis , Immunoglobulin G/metabolism , Male , Middle Aged , Spike Glycoprotein, Coronavirus/metabolism , Time Factors , Vaccination , Vaccines, Synthetic/immunology , Young Adult
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