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3.
Iran J Immunol ; 18(1): 82-92, 2021 03.
Article in English | MEDLINE | ID: covidwho-2067500

ABSTRACT

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rapidly transmits in general population, mainly between health-care workers (HCWs) who are in close contact with patients. OBJECTIVE: To study the seropositivity of HCWs as a high-risk group compared to general population. METHODS: 72 samples were obtained from HCWs working in Masih Daneshvari hospital as one of the main COVID-19 admission centers in Tehran, during April 4 to 6, 2020. Also we collected 2021 blood samples from general population. The SARS-CoV-2 specific IgM, and IgG antibodies in the collected serum specimens were measured by commercial ELISA kits. RESULTS: Based on the clinical manifestations, 25.0%, 47.2%, and 27.8% of HCWs were categorized as symptomatic with typical symptoms, symptomatic with atypical symptoms, and asymptomatic, respectively. Symptomatic individuals with typical and atypical symptoms were 63.2% and 36.8% positive in RT-PCR test, respectively. Anti-SARS-CoV-2 IgM and IgG antibodies were detected in 15.3% and 27.8% of HCWs samples, respectively. Antibody testing in the general population indicated that SARS-CoV-2 specific IgM and IgG were found in (162/2021) 8%, and (290/2021) 14.4%, respectively. The frequency of positive cases of IgM and IgG were significantly increased in HCWs compared to general population (p= 0.028 for IgM and p= 0.002 for IgG). CONCLUSION: The frequency of SARS-CoV-2 specific antibodies in HCWs was higher than general population indicating a higher viral transmission via close exposure with COVID-19 patients.


Subject(s)
Antibodies, Viral/blood , COVID-19 Serological Testing , COVID-19/diagnosis , Health Personnel , Occupational Health , SARS-CoV-2/immunology , Adult , Aged , Biomarkers/blood , COVID-19/epidemiology , COVID-19/immunology , COVID-19/virology , Cross-Sectional Studies , Female , Host-Pathogen Interactions , Humans , Infectious Disease Transmission, Patient-to-Professional , Iran/epidemiology , Male , Middle Aged , Occupational Exposure , Predictive Value of Tests , Risk Factors , Seroepidemiologic Studies , Time Factors , Young Adult
4.
PLoS One ; 17(2): e0262515, 2022.
Article in English | MEDLINE | ID: covidwho-1688746

ABSTRACT

BACKGROUND: Following the full re-opening of schools in England and emergence of the SARS-CoV-2 Alpha variant, we investigated the risk of SARS-CoV-2 infection in students and staff who were contacts of a confirmed case in a school bubble (school groupings with limited interactions), along with their household members. METHODS: Primary and secondary school bubbles were recruited into sKIDsBUBBLE after being sent home to self-isolate following a confirmed case of COVID-19 in the bubble. Bubble participants and their household members were sent home-testing kits comprising nasal swabs for RT-PCR testing and whole genome sequencing, and oral fluid swabs for SARS-CoV-2 antibodies. RESULTS: During November-December 2020, 14 bubbles were recruited from 7 schools, including 269 bubble contacts (248 students, 21 staff) and 823 household contacts (524 adults, 299 children). The secondary attack rate was 10.0% (6/60) in primary and 3.9% (4/102) in secondary school students, compared to 6.3% (1/16) and 0% (0/1) among staff, respectively. The incidence rate for household contacts of primary school students was 6.6% (12/183) and 3.7% (1/27) for household contacts of primary school staff. In secondary schools, this was 3.5% (11/317) and 0% (0/1), respectively. Household contacts were more likely to test positive if their bubble contact tested positive although there were new infections among household contacts of uninfected bubble contacts. INTERPRETATION: Compared to other institutional settings, the overall risk of secondary infection in school bubbles and their household contacts was low. Our findings are important for developing evidence-based infection prevention guidelines for educational settings.


Subject(s)
COVID-19/epidemiology , COVID-19/transmission , Adolescent , Adult , Antibodies, Viral/analysis , COVID-19/virology , Child , Contact Tracing , England/epidemiology , Female , Humans , Incidence , Male , Nasopharynx/virology , Prospective Studies , RNA, Viral/analysis , RNA, Viral/metabolism , Reverse Transcriptase Polymerase Chain Reaction , SARS-CoV-2/genetics , SARS-CoV-2/immunology , SARS-CoV-2/isolation & purification , Schools/statistics & numerical data , Students/statistics & numerical data
5.
J Clin Invest ; 132(19)2022 10 03.
Article in English | MEDLINE | ID: covidwho-2064380

ABSTRACT

The SARS-CoV-2 vaccine NVX-CoV2373 is a protein-based vaccine that might circumvent the difficulties in distributing mRNA vaccines to regions with limited access to cold-chain and refrigeration. However, the NVX-CoV2373-induced T cell and antibody responses remain poorly understood. In this issue of the JCI, Moderbacher et al. characterized SARS-CoV-2-specific CD4+ and CD8+ T cell responses elicited by one or two doses of NVX-CoV2373 in individuals enrolled in a phase I/IIa trial. Substantially increased spike-specific CD4+ and T follicular helper cells were found after the first or second vaccine dose, with some individuals developing a modest spike-specific CD8+ T cell response. Correlation analysis revealed an association between spike-specific CD4+ T cells and neutralizing antibody titers. Notably, preexisting T cell immunity showed negligible effects on NVX-CoV2373-induced T cell responses. These findings indicate that the protein-based vaccine NVX-CoV2373 induces robust T cell immunity capable of recognizing SARS-CoV-2 antigens and supporting humoral immune responses.


Subject(s)
COVID-19 Vaccines , COVID-19 , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines/immunology , Clinical Trials, Phase I as Topic , Clinical Trials, Phase II as Topic , Humans , Immunity, Humoral , SARS-CoV-2/immunology
6.
Science ; 378(6616): 128-131, 2022 10 14.
Article in English | MEDLINE | ID: covidwho-2063972

ABSTRACT

SARS-CoV-2 wields versatile proteins to foil our immune system's counterattack.


Subject(s)
COVID-19 , SARS-CoV-2 , Viral Proteins , Humans , COVID-19/immunology , SARS-CoV-2/immunology , Viral Proteins/immunology
10.
BMC Pregnancy Childbirth ; 22(1): 730, 2022 Sep 25.
Article in English | MEDLINE | ID: covidwho-2043117

ABSTRACT

BACKGROUND: The use of COVID-19 convalescent plasma (CCP) for the treatment of SARS-CoV-2 infection in pregnancy is intriguing in view of its safety profile in pregnancy and historical precedence of the use of plasma for other viral illnesses. This study aimed to evaluate the use of CCP in pregnant women with early COVID-19 infection. METHODS: This is a retrospective case series study. We have included seven pregnant women admitted with early COVID-19 infection to a tertiary care hospital, Latifa Maternity Hospital in Dubai, United Arab Emirates between 12 February and 04 March 2021 and who consented to receive COVID-19 convalescent plasma as part of their treatment plan. Main outcomes measured were clinical and radiological features, laboratory tests, WHO clinical progression scale pre and post treatment, and maternal, fetal outcomes. COVID-19 clinical severity was classified according to the NIH guidelines for criteria of SARS-CoV-2. For the radiological features, a modified chest X-ray scoring system was used where each lung was divided into 6 zones (3 on each side upper, middle, and lower). Opacities were classified into reticular, ground glass, patchy and dense consolidations patterns. RESULTS: Seven pregnant women with early COVID-19 were enrolled in this study, their mean age was 28 years (SD 3.6). Four had comorbidities: 2 with diabetes, 1 with asthma, and 1 was obese. Five patients were admitted with a WHO clinical progression score of 4 (hospitalized; with no oxygen therapy) and 2 with a score of 5 (hospitalized; oxygen by mask/nasal prongs). Upon follow up on day 10, 6 patients had a WHO score of 1 or 2 (asymptomatic/mild symptoms) indicating clinical recovery. Adverse reactions were reported in 2 patients, one reported a mild skin rash, and another developed transfusion related circulatory overload. All patients were discharged alive. CONCLUSION: CCP seems to be a promising modality of treating COVID-19 infected pregnant women. However, further studies are needed to ascertain the efficacy of CCP in preventing progressive disease in the management of COVID-19 infection in pregnant women.


Subject(s)
COVID-19 , Immunization, Passive , Pregnancy Complications, Infectious , Adult , COVID-19/immunology , COVID-19/therapy , COVID-19/virology , Female , Hospitals, Maternity , Humans , Immunization, Passive/adverse effects , Patient Discharge , Pregnancy , Pregnancy Complications, Infectious/immunology , Pregnancy Complications, Infectious/therapy , Pregnancy Complications, Infectious/virology , Retrospective Studies , SARS-CoV-2/immunology , Tertiary Care Centers , Treatment Outcome , United Arab Emirates
12.
Sci Rep ; 12(1): 15612, 2022 09 16.
Article in English | MEDLINE | ID: covidwho-2036890

ABSTRACT

Many therapeutic antibodies (Abs) and mRNA vaccines, both targeting SARS-CoV-2 spike protein (S-protein), have been developed and approved in order to combat the ongoing COVID-19 pandemic. In consideration of these developments, a common concern has been the potential for Ab-dependent enhancement (ADE) of infection caused by inoculated or induced Abs. Although the preventive and therapeutic effects of these Abs are obvious, little attention has been paid to the influence of the remaining and dwindling anti-S-protein Abs in vivo. Here, we demonstrate that certain monoclonal Abs (mAbs) approved as therapeutic neutralizing anti-S-protein mAbs for human usage have the potential to cause ADE in a narrow range of Ab concentrations. Although sera collected from mRNA-vaccinated individuals exhibited neutralizing activity, some sera gradually exhibited dominance of ADE activity in a time-dependent manner. None of the sera examined exhibited neutralizing activity against infection with the Omicron strain. Rather, some ADE of Omicron infection was observed in some sera. These results suggest the possible emergence of adverse effects caused by these Abs in addition to the therapeutic or preventive effect.


Subject(s)
Antibody-Dependent Enhancement , COVID-19 Vaccines , COVID-19 , Immune Sera , SARS-CoV-2 , Angiotensin-Converting Enzyme 2 , Antibodies, Viral , COVID-19/immunology , COVID-19/prevention & control , COVID-19/therapy , COVID-19 Vaccines/immunology , Humans , Immunization, Passive , Pandemics , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology
13.
Curr Opin Immunol ; 78: 102252, 2022 Oct.
Article in English | MEDLINE | ID: covidwho-2031214

ABSTRACT

The outbreak of the COVID-19 pandemic one year after the centennial of the 1918 influenza pandemic reaffirms the catastrophic impact respiratory viruses can have on global health and economy. A key feature of SARS-CoV-2 and influenza A viruses (IAV) is their remarkable ability to suppress or dysregulate human immune responses. Here, we summarize the growing knowledge about the interplay of SARS-CoV-2 and antiviral innate immunity, with an emphasis on the regulation of type-I or -III interferon responses that are critically implicated in COVID-19 pathogenesis. Furthermore, we draw parallels to IAV infection and discuss shared innate immune sensing mechanisms and the respective viral countermeasures.


Subject(s)
COVID-19 , Influenza, Human , Interferons , SARS-CoV-2 , Humans , COVID-19/immunology , COVID-19/metabolism , COVID-19/virology , Immunity, Innate , Influenza A virus/immunology , Influenza, Human/immunology , Influenza, Human/metabolism , Influenza, Human/virology , Interferons/immunology , Pandemics , SARS-CoV-2/immunology
16.
J Virol ; 96(18): e0133722, 2022 09 28.
Article in English | MEDLINE | ID: covidwho-2019728

ABSTRACT

COVID-19 and influenza are both highly contagious respiratory diseases that have been serious threats to global public health. It is necessary to develop a bivalent vaccine to control these two infectious diseases simultaneously. In this study, we generated three attenuated replicating recombinant vesicular stomatitis virus (rVSV)-based vaccine candidates against both SARS-CoV-2 and influenza viruses. These rVSV-based vaccines coexpress SARS-CoV-2 Delta spike protein (SP) bearing the C-terminal 17 amino acid (aa) deletion (SPΔC) and I742A point mutation, or the SPΔC with a deletion of S2 domain, or the RBD domain, and a tandem repeat harboring four copies of the highly conserved influenza M2 ectodomain (M2e) that fused with the Ebola glycoprotein DC-targeting/activation domain. Animal immunization studies have shown that these rVSV bivalent vaccines induced efficient humoral and cellular immune responses against both SARS-CoV-2 SP and influenza M2 protein, including high levels of neutralizing antibodies against SARS-CoV-2 Delta and other variant SP-pseudovirus infections. Importantly, immunization of the rVSV bivalent vaccines effectively protected hamsters or mice against the challenges of SARS-CoV-2 Delta variant and lethal H1N1 and H3N2 influenza viruses and significantly reduced respiratory viral loads. Overall, this study provides convincing evidence for the high efficacy of this bivalent vaccine platform to be used and/or easily adapted to produce new vaccines against new or reemerging SARS-CoV-2 variants and influenza A virus infections. IMPORTANCE Given that both COVID-19 and influenza are preferably transmitted through respiratory droplets during the same seasons, it is highly advantageous to develop a bivalent vaccine that could simultaneously protect against both COVID-19 and influenza. In this study, we generated the attenuated replicating recombinant vesicular stomatitis virus (rVSV)-based vaccine candidates that target both spike protein of SARS-Cov-2 Delta variant and the conserved influenza M2 domain. Importantly, these vaccine candidates effectively protected hamsters or mice against the challenges of SARS-CoV-2 Delta variant and lethal H1N1 and H3N2 influenza viruses and significantly reduced respiratory viral loads.


Subject(s)
COVID-19 , Influenza A Virus, H1N1 Subtype , Influenza Vaccines , Influenza, Human , Vaccines, Combined , Vesicular Stomatitis , Amino Acids/genetics , Animals , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , Cricetinae , Glycoproteins/genetics , Glycoproteins/immunology , Humans , Influenza A Virus, H3N2 Subtype , Influenza Vaccines/genetics , Influenza Vaccines/immunology , Influenza, Human/prevention & control , Mice , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Vaccines, Combined/immunology , Vaccines, Synthetic/genetics , Vesiculovirus/immunology
19.
Nature ; 611(7934): 139-147, 2022 11.
Article in English | MEDLINE | ID: covidwho-2016757

ABSTRACT

Severe SARS-CoV-2 infection1 has been associated with highly inflammatory immune activation since the earliest days of the COVID-19 pandemic2-5. More recently, these responses have been associated with the emergence of self-reactive antibodies with pathologic potential6-10, although their origins and resolution have remained unclear11. Previously, we and others have identified extrafollicular B cell activation, a pathway associated with the formation of new autoreactive antibodies in chronic autoimmunity12,13, as a dominant feature of severe and critical COVID-19 (refs. 14-18). Here, using single-cell B cell repertoire analysis of patients with mild and severe disease, we identify the expansion of a naive-derived, low-mutation IgG1 population of antibody-secreting cells (ASCs) reflecting features of low selective pressure. These features correlate with progressive, broad, clinically relevant autoreactivity, particularly directed against nuclear antigens and carbamylated proteins, emerging 10-15 days after the onset of symptoms. Detailed analysis of the low-selection compartment shows a high frequency of clonotypes specific for both SARS-CoV-2 and autoantigens, including pathogenic autoantibodies against the glomerular basement membrane. We further identify the contraction of this pathway on recovery, re-establishment of tolerance standards and concomitant loss of acute-derived ASCs irrespective of antigen specificity. However, serological autoreactivity persists in a subset of patients with postacute sequelae, raising important questions as to the contribution of emerging autoreactivity to continuing symptomology on recovery. In summary, this study demonstrates the origins, breadth and resolution of autoreactivity in severe COVID-19, with implications for early intervention and the treatment of patients with post-COVID sequelae.


Subject(s)
Autoantibodies , B-Lymphocytes , COVID-19 , Humans , Autoantibodies/immunology , B-Lymphocytes/immunology , B-Lymphocytes/pathology , COVID-19/immunology , COVID-19/pathology , COVID-19/physiopathology , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity , Immunoglobulin G/immunology , Single-Cell Analysis , Autoantigens/immunology , Basement Membrane/immunology
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