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2.
MMWR Morb Mortal Wkly Rep ; 70(40): 1425-1426, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: covidwho-1456570

RESUMO

According to sequencing data reported by CDC, the highly transmissible B.1.617.2 (Delta) variant of SARS-CoV-2, the virus that causes COVID-19, has been the predominant lineage circulating in Louisiana since the week of June 20, 2021 (1). In Louisiana, the increased spread of the Delta variant corresponded with the start of the state's fourth and largest increase in average daily COVID-19 incidence to date (1,2). This report describes COVID-19 outbreaks in Louisiana youth summer camps as the Delta variant became the predominant lineage during June-July 2021. This activity was reviewed by the Louisiana Department of Health (LDH) and was conducted consistent with applicable state law and LDH policy.


Assuntos
COVID-19/epidemiologia , Acampamento , Surtos de Doenças , Adolescente , Adulto , COVID-19/prevenção & controle , COVID-19/transmissão , COVID-19/virologia , Criança , Pré-Escolar , Busca de Comunicante , Humanos , Louisiana/epidemiologia , Pessoa de Meia-Idade , SARS-CoV-2/isolamento & purificação , Estações do Ano , Adulto Jovem
3.
MMWR Morb Mortal Wkly Rep ; 70(40): 1415-1419, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: covidwho-1456568

RESUMO

Data from observational studies demonstrate that variants of SARS-CoV-2, the virus that causes COVID-19, have evolved rapidly across many countries (1,2). The SARS-CoV-2 B.1.617.2 (Delta) variant of concern is more transmissible than previously identified variants,* and as of September 2021, is the predominant variant in the United States.† Studies characterizing the distribution and severity of illness caused by SARS-CoV-2 variants, particularly the Delta variant, are limited in the United States (3), and are subject to limitations related to study setting, specimen collection, study population, or study period (4-7). This study used whole genome sequencing (WGS) data on SARS-CoV-2-positive specimens collected across Kaiser Permanente Southern California (KPSC), a large integrated health care system, to describe the distribution and risk of hospitalization associated with SARS-CoV-2 variants during March 4-July 21, 2021, by patient vaccination status. Among 13,039 SARS-CoV-2-positive specimens identified from KPSC patients during this period, 6,798 (52%) were sequenced and included in this report. Of these, 5,994 (88%) were collected from unvaccinated persons, 648 (10%) from fully vaccinated persons, and 156 (2%) from partially vaccinated persons. Among all sequenced specimens, the weekly percentage of B.1.1.7 (Alpha) variant infections increased from 20% to 67% during March 4-May 19, 2021. During April 15-July 21, 2021, the weekly percentage of Delta variant infections increased from 0% to 95%. During March 4-July 21, 2021, the weekly percentage of variants was similar among fully vaccinated and unvaccinated persons, but the Delta variant was more commonly identified among vaccinated persons then unvaccinated persons overall, relative to other variants. The Delta variant was more prevalent among younger persons, with the highest percentage (55%) identified among persons aged 18-44 years. Infections attributed to the Delta variant were also more commonly identified among non-Hispanic Black persons, relative to other variants. These findings reinforce the importance of continued monitoring of SARS-CoV-2 variants and implementing multiple COVID-19 prevention strategies, particularly during the current period in which Delta is the predominant variant circulating in the United States.


Assuntos
COVID-19/diagnóstico , COVID-19/virologia , Prestação Integrada de Cuidados de Saúde , SARS-CoV-2/isolamento & purificação , Adolescente , Adulto , Idoso , COVID-19/epidemiologia , California/epidemiologia , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
BMC Infect Dis ; 21(1): 665, 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: covidwho-1455925

RESUMO

BACKGROUND: As SARS-CoV-2 testing expands, particularly to widespread asymptomatic testing, high sensitivity point-of-care PCR platforms may optimise potential benefits from pooling multiple patients' samples. METHOD: We tested patients and asymptomatic citizens for SARS-CoV-2, exploring the efficiency and utility of CovidNudge (i) for detection in individuals' sputum (compared to nasopharyngeal swabs), (ii) for detection in pooled sputum samples, and (iii) by modelling roll out scenarios for pooled sputum testing. RESULTS: Across 295 paired samples, we find no difference (p = 0.1236) in signal strength for sputum (mean amplified replicates (MAR) 25.2, standard deviation (SD) 14.2, range 0-60) compared to nasopharyngeal swabs (MAR 27.8, SD 12.4, range 6-56). At 10-sample pool size we find some drop in absolute strength of signal (individual sputum MAR 42.1, SD 11.8, range 13-60 vs. pooled sputum MAR 25.3, SD 14.6, range 1-54; p < 0.0001), but only marginal drop in sensitivity (51/53,96%). We determine a limit of detection of 250 copies/ml for an individual test, rising only four-fold to 1000copies/ml for a 10-sample pool. We find optimal pooled testing efficiency to be a 12-3-1-sample model, yet as prevalence increases, pool size should decrease; at 5% prevalence to maintain a 75% probability of negative first test, 5-sample pools are optimal. CONCLUSION: We describe for the first time the use of sequentially dipped sputum samples for rapid pooled point of care SARS-CoV-2 PCR testing. The potential to screen asymptomatic cohorts rapidly, at the point-of-care, with PCR, offers the potential to quickly identify and isolate positive individuals within a population "bubble".


Assuntos
Teste para COVID-19/métodos , COVID-19/diagnóstico , COVID-19/virologia , Testes Imediatos , SARS-CoV-2/isolamento & purificação , Escarro/virologia , Testes Diagnósticos de Rotina , Humanos , Limite de Detecção , Nasofaringe/virologia , Sensibilidade e Especificidade , Carga Viral
6.
J Med Virol ; 93(10): 6054-6058, 2021 10.
Artigo em Inglês | MEDLINE | ID: covidwho-1453608

RESUMO

The rapid spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant of concern with higher infectivity has already resulted in the enormous increase in infection cases worldwide. We report an unrecognized introduction of the variant B.1.1.7 in Gabon in December 2020, which was the initial phase of the variant introduction to Africa. The B.1.1.7 variant was also detected in a hospitalized patient in January 2021, indicating a rapid spread of the variant in Gabon since its first detection. Phylogenetic analysis revealed that the detected B.1.1.7 variants originated from the distinct regions, strongly suggesting that the B.1.1.7 variant had been repeatedly introduced to Gabon since December 2020. These results provide insights on the unrecognized risks of infections with variants of concern, and show the necessity to conduct continuous genomic monitoring for immediate alert and control of novel SARS-CoV-2 variant infections.


Assuntos
COVID-19/epidemiologia , COVID-19/transmissão , SARS-CoV-2/genética , África Central/epidemiologia , COVID-19/virologia , Genoma Viral , Humanos , Mutação , Filogenia , RNA Viral , Sequenciamento Completo do Genoma
7.
J Med Virol ; 93(10): 5805-5815, 2021 10.
Artigo em Inglês | MEDLINE | ID: covidwho-1453606

RESUMO

Aggressive immune response, due to overexpressed proinflammatory molecules, has been characterized in coronavirus disease 2019 (COVID-19) patients. Some of those mediators have a dual and opposite role on immune systems at play behind differential disease severities. We investigated the expression of some cytokines and chemokines in COVID-19 patients in Bangladesh. We diagnosed the patients by detecting severe acute respiratory syndrome coronavirus 2 RNA in nasal swab samples by the real-time RT-PCR method. Thirty adult patients were preselected based on their disease severities and grouped into mild, moderate, and severe cases. Nine healthy volunteers participated in this study as a control. Relative expression of nine cytokines/chemokine in total leukocytes was semi-quantified in SYBRgreen-based real-time quantitative reverse-transcriptase polymerase chain reaction. We performed statistical tests on transformed log data using SPSS 24.0. At the onset of symptoms (Day 1), angiotensin-converting enzyme 2 (ACE2) (p < 0.05) and interleukin (IL)-6 (p > 0.05) were upregulated in all COVID-19 groups, although the expression levels did not significantly correlate with disease severities. However, expressions of IL-6, monocyte chemotactic protein-1, macrophage inflammatory protein-1α, tumor necrosis factor-α (TNF-α), RANTES (regulated upon activation, normal T cell expressed and secreted), and ACE2, on Day 14, were positively correlated with disease severities. Relative viral load at Day 1 showed no significant correlation with cytokine expression but had a significant positive correlation with RANTES and ACE2 expression on Day 14 (p < 0.05). Male patients had a higher level of IL-6 than female patients on Day 1 (p < 0.05). All COVID-19 patients showed upregulated cytokines and chemokines on Day 14 compared to Day 1 except TNF-α. Female patients had a higher expression of ACE2 and IL-12 on Day 14. Upregulated cytokines/chemokines at the convalescent stage, especially IL-6, may help in targeting anticytokine therapy in post-COVID-19 patients' management.


Assuntos
COVID-19/diagnóstico , Citocinas/sangue , Adulto , Bangladesh/epidemiologia , COVID-19/epidemiologia , COVID-19/imunologia , COVID-19/virologia , Quimiocinas/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/isolamento & purificação , Índice de Gravidade de Doença , Carga Viral
10.
Front Endocrinol (Lausanne) ; 12: 705214, 2021.
Artigo em Inglês | MEDLINE | ID: covidwho-1448725

RESUMO

The ongoing coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is a global health crisis affecting millions of people worldwide. SARS-CoV-2 enters the host cells by binding to angiotensin-converting enzyme 2 (ACE2) after being cleaved by the transmembrane protease serine 2 (TMPRSS2). In addition to the lung, gastrointestinal tract and kidney, ACE2 is also extensively expressed in endocrine tissues, including the pituitary and adrenal glands. Although glucocorticoids could play a central role as immunosuppressants during the cytokine storm, they can have both stimulating and inhibitory effects on immune response, depending on the timing of their administration and their circulating levels. Patients with adrenal insufficiency (AI) or Cushing's syndrome (CS) are therefore vulnerable groups in relation to COVID-19. Additionally, patients with adrenocortical carcinoma (ACC) could also be more vulnerable to COVID-19 due to the immunosuppressive state caused by the cancer itself, by secreted glucocorticoids, and by anticancer treatments. This review comprehensively summarizes the current literature on susceptibility to and outcome of COVID-19 in AI, CS and ACC patients and emphasizes potential pathophysiological mechanisms of susceptibility to COVID-19 as well as the management of these patients in case of SARS-CoV-2. Finally, by performing an in silico analysis, we describe the mRNA expression of ACE2, TMPRSS2 and the genes encoding their co-receptors CTSB, CTSL and FURIN in normal adrenal and adrenocortical tumors (both adenomas and carcinomas).


Assuntos
COVID-19/complicações , COVID-19/virologia , Glucocorticoides/administração & dosagem , Insuficiência Adrenal/complicações , Insuficiência Adrenal/imunologia , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/imunologia , Animais , COVID-19/genética , COVID-19/imunologia , Síndrome de Cushing/complicações , Síndrome de Cushing/imunologia , Humanos , Neoplasias/complicações , Neoplasias/imunologia , SARS-CoV-2/genética , SARS-CoV-2/fisiologia
12.
Chem Pharm Bull (Tokyo) ; 69(10): 984-988, 2021.
Artigo em Inglês | MEDLINE | ID: covidwho-1445702

RESUMO

Membrane-based rapid test reagents including immunochromatography are widely used in clinical practice. Recently, high-sensitive reagents based on the immunochromatography method, such as silver amplification method and time resolved fluorescence method for influenza testing, has been developed and early confirmation of infection can be achieved. Furthermore, genetic testing, automated all the steps from extraction till detection, is getting popular. Genetic testing of mycoplasma by Smart Gene Myco system and Coronavirus disease 2019 (COVID-19) test is a good example of membrane-based rapid test reagents. This system uses silica particle-containing membrane filter and enable to shorten the assay time by automates pre-treatment process for removing contamination substances in the sample which affect polymerase-chain-reaction amplification. We hope utilized genetic testing application will help quick confirmation of COVID-19 positive patient and prevent the collapse of medical system under COVID-19 development.


Assuntos
Cromatografia de Afinidade/métodos , Sistemas Automatizados de Assistência Junto ao Leito , COVID-19/diagnóstico , COVID-19/virologia , Teste para COVID-19 , Testes Genéticos , Humanos , Influenza Humana/diagnóstico , Influenza Humana/virologia , Orthomyxoviridae/genética , Orthomyxoviridae/isolamento & purificação , Reação em Cadeia da Polimerase , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação
13.
Microvasc Res ; 138: 104232, 2021 11.
Artigo em Inglês | MEDLINE | ID: covidwho-1446976

RESUMO

The mechanisms by which the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) induces neurological complications remain to be elucidated. We aimed to identify possible effects of hypoxia on the expression of SARS-CoV-2 cell entry mediators, angiotensin-converting enzyme 2 (ACE2) receptor and transmembrane protease serine 2 (TMPRSS2) protein, in human brain endothelial cells, in vitro. hCMEC/D3 cells were exposed to different oxygen tensions: 20% (Control group), 8% or 2% O2 (Hypoxia groups). Cells were harvested 6-, 24- and 48 h following hypoxic challenge for assessment of mRNA and protein, using qPCR and Western Blot. The response of the brain endothelial cells to hypoxia was replicated using modular incubator chambers. We observed an acute increase (6 h, p < 0.05), followed by a longer-term decrease (48 h, p < 0.05) in ACE2 mRNA and protein expression, accompanied by reduced expression of TMPRSS2 protein levels (48 h, p < 0.05) under the more severe hypoxic condition (2% O2). No changes in levels of von Willebrand Factor (vWF - an endothelial cell damage marker) or interleukin 6 (IL-6 - a pro-inflammatory cytokine) mRNA were observed. We conclude that hypoxia regulates brain endothelial cell ACE2 and TMPRSS2 expression in vitro, which may indicate human brain endothelial susceptibility to SARS-CoV-2 infection and subsequent brain sequelae.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , Encéfalo/irrigação sanguínea , COVID-19/virologia , Células Endoteliais/virologia , SARS-CoV-2/patogenicidade , Serina Endopeptidases/metabolismo , Internalização do Vírus , Enzima de Conversão de Angiotensina 2/genética , COVID-19/enzimologia , Hipóxia Celular , Linhagem Celular , Células Endoteliais/enzimologia , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno , Humanos , Serina Endopeptidases/genética
14.
Biochem Biophys Res Commun ; 574: 14-19, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: covidwho-1446453

RESUMO

Following the initial surges of the Alpha (B.1.1.7) and the Beta (B.1.351) variants, a more infectious Delta variant (B.1.617.2) is now surging, further deepening the health crises caused by the pandemic. The sharp rise in cases attributed to the Delta variant has made it especially disturbing and is a variant of concern. Fortunately, current vaccines offer protection against known variants of concern, including the Delta variant. However, the Delta variant has exhibited some ability to dodge the immune system as it is found that neutralizing antibodies from prior infections or vaccines are less receptive to binding with the Delta spike protein. Here, we investigated the structural changes caused by the mutations in the Delta variant's receptor-binding interface and explored the effects on binding with the ACE2 receptor as well as with neutralizing antibodies. We find that the receptor-binding ß-loop-ß motif adopts an altered but stable conformation causing separation in some of the antibody binding epitopes. Our study shows reduced binding of neutralizing antibodies and provides a possible mechanism for the immune evasion exhibited by the Delta variant.


Assuntos
Enzima de Conversão de Angiotensina 2/imunologia , COVID-19/imunologia , Evasão da Resposta Imune/imunologia , Mutação/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Aminoácidos/genética , Aminoácidos/imunologia , Aminoácidos/metabolismo , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Anticorpos Antivirais/imunologia , Sítios de Ligação/genética , Sítios de Ligação/imunologia , COVID-19/metabolismo , COVID-19/virologia , Humanos , Evasão da Resposta Imune/genética , Simulação de Dinâmica Molecular , Mutação/genética , Testes de Neutralização , Ligação Proteica , Domínios Proteicos , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética
15.
Laeknabladid ; 107(10): 460-468, 2021 Oct.
Artigo em Islandês | MEDLINE | ID: covidwho-1444585

RESUMO

Introduction Infections due to COVID-19 can lead to life threatening pneumonia. Accompanying severe disease are more prominent pulmonary changes on Computed Tomography (CT) scan of the chest. The goal of this study was to describe pulmonary CT changes during acute COVID-19 and at follow up and whether the extent of changes correlate with severity of illness, demographics or other risk factors. Materials and methods Included in this study are all individuals that had confirmed COVID-19 and came for a follow up CT of the chest at Landspitali from May to September 2020. Information regarding medical history was obtained retrospectively from medical charts. All CT scans were reviewed using an international staging system to evaluate the extent of lung changes. Results Eighty-five patients with a mean age of 59 years were included in the study. Sixty patients (71%) were hospitalized during the acute phase and 18 (21%) were admitted to the ICU. During the acute phase more pronounced lung involvement was seen in males and patients admitted to the ICU. At follow-up females had less lung involvement but there was a significant relationship between a higher CT score and age, ICU admissions and days in the ICU. Full recovery was seen at follow-up CT in 31% of patients (median 68,5 days between acute and follow-up imaging). Conclusion Patients with severe COVID-19 have more pronounced lung involvement on CT than patients with milder disease during the acute phase and follow-up. Older patients and males are at greater risk of acute and persistent COVID-19 related lung changes.


Assuntos
COVID-19/diagnóstico por imagem , Pulmão/diagnóstico por imagem , SARS-CoV-2/patogenicidade , Tomografia Computadorizada por Raios X , Adulto , Fatores Etários , Idoso , COVID-19/terapia , COVID-19/virologia , Bases de Dados Factuais , Feminino , Hospitalização , Interações Hospedeiro-Patógeno , Humanos , Islândia , Pulmão/virologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Fatores Sexuais
17.
PLoS Pathog ; 17(8): e1009865, 2021 08.
Artigo em Inglês | MEDLINE | ID: covidwho-1443861

RESUMO

While evidence exists supporting the potential for aerosol transmission of SARS-CoV-2, the infectious dose by inhalation remains unknown. In the present study, the probability of infection following inhalation of SARS-CoV-2 was dose-dependent in a nonhuman primate model of inhalational COVID-19. The median infectious dose, assessed by seroconversion, was 52 TCID50 (95% CI: 23-363 TCID50), and was significantly lower than the median dose for fever (256 TCID50, 95% CI: 102-603 TCID50), resulting in a group of animals that developed an immune response post-exposure but did not develop fever or other clinical signs of infection. In a subset of these animals, virus was detected in nasopharyngeal and/or oropharyngeal swabs, suggesting that infected animals without signs of disease are able to shed virus and may be infectious, which is consistent with reports of asymptomatic spread in human cases of COVID-19. These results suggest that differences in exposure dose may be a factor influencing disease presentation in humans, and reinforce the importance of public health measures that limit exposure dose, such as social distancing, masking, and increased ventilation. The dose-response data provided by this study are important to inform disease transmission and hazard modeling, and, ultimately, mitigation strategies. Additionally, these data will be useful to inform dose selection in future studies examining the efficacy of therapeutics and vaccines against inhalational COVID-19, and as a baseline in healthy, young adult animals for assessment of the importance of other factors, such as age, comorbidities, and viral variant, on the infectious dose and disease presentation.


Assuntos
COVID-19/transmissão , COVID-19/virologia , Macaca fascicularis , Soroconversão , Animais , Chlorocebus aethiops , Modelos Animais de Doenças , Feminino , Febre/virologia , Exposição por Inalação , Masculino , Células Vero , Carga Viral
18.
Physiol Rev ; 101(4): 1457-1486, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: covidwho-1443666

RESUMO

This medical review addresses the hypothesis that CD38/NADase is at the center of a functional axis (i.e., intracellular Ca2+ mobilization/IFNγ response/reactive oxygen species burst) driven by severe acute respiratory syndrome coronavirus 2 infection, as already verified in respiratory syncytial virus pathology and CD38 activity in other cellular settings. Key features of the hypothesis are that 1) the substrates of CD38 (e.g., NAD+ and NADP+) are depleted by viral-induced metabolic changes; 2) the products of the enzymatic activity of CD38 [e.g., cyclic adenosine diphosphate-ribose (ADPR)/ADPR/nicotinic acid adenine dinucleotide phosphate] and related enzymes [e.g., poly(ADP-ribose)polymerase, Sirtuins, and ADP-ribosyl hydrolase] are involved in the anti-viral and proinflammatory response that favors the onset of lung immunopathology (e.g., cytokine storm and organ fibrosis); and 3) the pathological changes induced by this kinetic mechanism may be reduced by distinct modulators of the CD38/NAD+ axis (e.g., CD38 blockers, NAD+ suppliers, among others). This view is supported by arrays of associative basic and applied research data that are herein discussed and integrated with conclusions reported by others in the field of inflammatory, immune, tumor, and viral diseases.


Assuntos
ADP-Ribosil Ciclase 1/metabolismo , COVID-19/metabolismo , Glicoproteínas de Membrana/metabolismo , SARS-CoV-2 , ADP-Ribosil Ciclase 1/genética , COVID-19/patologia , COVID-19/virologia , Regulação Enzimológica da Expressão Gênica , Humanos , Glicoproteínas de Membrana/genética
19.
Gigascience ; 10(9)2021 09 28.
Artigo em Inglês | MEDLINE | ID: covidwho-1443047

RESUMO

BACKGROUND: B-cell immunoglobulin repertoires with paired heavy and light chain can be determined by means of 10X single-cell V(D)J sequencing. Precise and quick analysis of 10X single-cell immunoglobulin repertoires remains a challenge owing to the high diversity of immunoglobulin repertoires and a lack of specialized software that can analyze such diverse data. FINDINGS: In this study, specialized software for 10X single-cell immunoglobulin repertoire analysis was developed. SCIGA (Single-Cell Immunoglobulin Repertoire Analysis) is an easy-to-use pipeline that performs read trimming, immunoglobulin sequence assembly and annotation, heavy and light chain pairing, statistical analysis, visualization, and multiple sample integration analysis, which is all achieved by using a 1-line command. Then SCIGA was used to profile the single-cell immunoglobulin repertoires of 9 patients with coronavirus disease 2019 (COVID-19). Four neutralizing antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were identified from these repertoires. CONCLUSIONS: SCIGA provides a complete and quick analysis for 10X single-cell V(D)J sequencing datasets. It can help researchers to interpret B-cell immunoglobulin repertoires with paired heavy and light chain.


Assuntos
Imunoglobulinas/metabolismo , Análise de Célula Única/métodos , Software , Anticorpos Monoclonais/química , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/metabolismo , COVID-19/patologia , COVID-19/virologia , Humanos , Imunoglobulinas/química , Imunoglobulinas/genética , SARS-CoV-2/imunologia , SARS-CoV-2/isolamento & purificação
20.
Nature ; 597(7878): 703-708, 2021 09.
Artigo em Inglês | MEDLINE | ID: covidwho-1442788

RESUMO

SARS-CoV-2 infections have surged across the globe in recent months, concomitant with considerable viral evolution1-3. Extensive mutations in the spike protein may threaten the efficacy of vaccines and therapeutic monoclonal antibodies4. Two signature spike mutations of concern are E484K, which has a crucial role in the loss of neutralizing activity of antibodies, and N501Y, a driver of rapid worldwide transmission of the B.1.1.7 lineage. Here we report the emergence of the variant lineage B.1.526 (also known as the Iota variant5), which contains E484K, and its rise to dominance in New York City in early 2021. This variant is partially or completely resistant to two therapeutic monoclonal antibodies that are in clinical use and is less susceptible to neutralization by plasma from individuals who had recovered from SARS-CoV-2 infection or serum from vaccinated individuals, posing a modest antigenic challenge. The presence of the B.1.526 lineage has now been reported in all 50 states in the United States and in many other countries. B.1.526 rapidly replaced earlier lineages in New York, with an estimated transmission advantage of 35%. These transmission dynamics, together with the relative antibody resistance of its E484K sub-lineage, are likely to have contributed to the sharp rise and rapid spread of B.1.526. Although SARS-CoV-2 B.1.526 initially outpaced B.1.1.7 in the region, its growth subsequently slowed concurrently with the rise of B.1.1.7 and ensuing variants.


Assuntos
COVID-19/virologia , SARS-CoV-2/crescimento & desenvolvimento , SARS-CoV-2/isolamento & purificação , Anticorpos Neutralizantes/imunologia , Humanos , Mutação , New York/epidemiologia , Filogenia , Filogeografia , Prevalência , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Estados Unidos/epidemiologia
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