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1.
Viruses ; 14(12)2022 12 09.
Article in English | MEDLINE | ID: covidwho-2155314

ABSTRACT

Since its first identification in Brazil, the variant of concern (VOC) Gamma has been associated with increased infection and transmission rates, hospitalizations, and deaths. Minas Gerais (MG), the second-largest populated Brazilian state with more than 20 million inhabitants, observed a peak of cases and deaths in March-April 2021. We conducted a surveillance study in 1240 COVID-19-positive samples from 305 municipalities distributed across MG's 28 Regional Health Units (RHU) between 1 March to 27 April 2021. The most common variant was the VOC Gamma (71.2%), followed by the variant of interest (VOI) zeta (12.4%) and VOC alpha (9.6%). Although the predominance of Gamma was found in most of the RHUs, clusters of Zeta and Alpha variants were observed. One Alpha-clustered RHU has a history of high human mobility from countries with Alpha predominance. Other less frequent lineages, such as P.4, P.5, and P.7, were also identified. With our genomic characterization approach, we estimated the introduction of Gamma on 7 January 2021, at RHU Belo Horizonte. Differences in mortality between the Zeta, Gamma and Alpha variants were not observed. We reinforce the importance of vaccination programs to prevent severe cases and deaths during transmission peaks.


Subject(s)
COVID-19 , Humans , Brazil/epidemiology , Retrospective Studies , COVID-19/epidemiology , SARS-CoV-2 , Genomics
2.
J Clin Virol Plus ; : 100103, 2022 Aug 17.
Article in English | MEDLINE | ID: covidwho-2028189

ABSTRACT

There is a massive demand to identify alternative methods to detect new cases of COVID-19 as well as to investigate the epidemiology of the disease. In many countries, importation of commercial kits poses a significant impact on their testing capacity and increases the costs for the public health system. We have developed an ELISA to detect IgG antibodies against SARS-CoV-2 using a recombinant viral nucleocapsid (rN) protein expressed in E. coli. Using a total of 894 clinical samples we showed that the rN-ELISA was able to detect IgG antibodies against SARS-CoV-2 with high sensitivity (97.5%) and specificity (96.3%) when compared to a commercial antibody test. After three external validation studies, we showed that the test accuracy was higher than 90%. The rN-ELISA IgG kit constitutes a convenient and specific method for the large-scale determination of SARS-CoV-2 antibodies in human sera with high reliability.

3.
Virus Evol ; 8(2): veac064, 2022 Jul.
Article in English | MEDLINE | ID: covidwho-1997080

ABSTRACT

The emergence and global dissemination of Severe Acute Respiratory Syndrome virus 2 (SARS-CoV-2) variants of concern (VOCs) have been described as the main factor driving the Coronavirus Disease 2019 pandemic. In Brazil, the Gamma variant dominated the epidemiological scenario during the first period of 2021. Many Brazilian regions detected the Delta variant after its first description and documented its spread. To monitor the introduction and spread of VOC Delta, we performed Polymerase Chain Reaction (PCR) genotyping and genome sequencing in ten regional sentinel units from June to October 2021 in the State of Minas Gerais (MG). We documented the introduction and spread of Delta, comprising 70 per cent of the cases 8 weeks later. Comparing the viral loads of the Gamma and Delta dominance periods, we provide additional evidence that the latter is more transmissible. The spread and dominance of Delta did not culminate in the increase in cases and deaths, suggesting that the vaccination may have restrained the epidemic growth. Analysis of 224 novel Delta genomes revealed that Rio de Janeiro state was the primary source for disseminating this variant in the state of MG. We present the establishment of Delta, providing evidence of its enhanced transmissibility and showing that this variant shift did not aggravate the epidemiological scenario in a high immunity setting.

4.
Nat Commun ; 13(1): 4831, 2022 08 17.
Article in English | MEDLINE | ID: covidwho-1991599

ABSTRACT

Both T cells and B cells have been shown to be generated after infection with SARS-CoV-2 yet protocols or experimental models to study one or the other are less common. Here, we generate a chimeric protein (SpiN) that comprises the receptor binding domain (RBD) from Spike (S) and the nucleocapsid (N) antigens from SARS-CoV-2. Memory CD4+ and CD8+ T cells specific for SpiN could be detected in the blood of both individuals vaccinated with Coronavac SARS-CoV-2 vaccine and COVID-19 convalescent donors. In mice, SpiN elicited a strong IFN-γ response by T cells and high levels of antibodies to the inactivated virus, but not detectable neutralizing antibodies (nAbs). Importantly, immunization of Syrian hamsters and the human Angiotensin Convertase Enzyme-2-transgenic (K18-ACE-2) mice with Poly ICLC-adjuvanted SpiN promotes robust resistance to the wild type SARS-CoV-2, as indicated by viral load, lung inflammation, clinical outcome and reduction of lethality. The protection induced by SpiN was ablated by depletion of CD4+ and CD8+ T cells and not transferred by antibodies from vaccinated mice. Finally, vaccination with SpiN also protects the K18-ACE-2 mice against infection with Delta and Omicron SARS-CoV-2 isolates. Hence, vaccine formulations that elicit effector T cells specific for the N and RBD proteins may be used to improve COVID-19 vaccines and potentially circumvent the immune escape by variants of concern.


Subject(s)
COVID-19 , SARS-CoV-2 , Animals , Antibodies, Neutralizing , Antibodies, Viral , CD8-Positive T-Lymphocytes , COVID-19/prevention & control , COVID-19 Vaccines , Humans , Mice , Nucleocapsid , Nucleocapsid Proteins , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus
5.
J Clin Virol Plus ; 2(3): 100101, 2022 Aug.
Article in English | MEDLINE | ID: covidwho-1977454

ABSTRACT

There is a massive demand to identify alternative methods to detect new cases of COVID-19 as well as to investigate the epidemiology of the disease. In many countries, importation of commercial kits poses a significant impact on their testing capacity and increases the costs for the public health system. We have developed an ELISA to detect IgG antibodies against SARS-CoV-2 using a recombinant viral nucleocapsid (rN) protein expressed in E. coli. Using a total of 894 clinical samples we showed that the rN-ELISA was able to detect IgG antibodies against SARS-CoV-2 with high sensitivity (97.5%) and specificity (96.3%) when compared to a commercial antibody test. After three external validation studies, we showed that the test accuracy was higher than 90%. The rN-ELISA IgG kit constitutes a convenient and specific method for the large-scale determination of SARS-CoV-2 antibodies in human sera with high reliability.

6.
Front Med (Lausanne) ; 9: 844728, 2022.
Article in English | MEDLINE | ID: covidwho-1834450

ABSTRACT

Background: Nitazoxanide exerts antiviral activity in vitro and in vivo and anti-inflammatory effects, but its impact on patients hospitalized with COVID-19 pneumonia is uncertain. Methods: A multicentre, randomized, double-blind, placebo-controlled trial was conducted in 19 hospitals in Brazil. Hospitalized adult patients requiring supplemental oxygen, with COVID-19 symptoms and a chest computed tomography scan suggestive of viral pneumonia or positive RT-PCR test for COVID-19 were enrolled. Patients were randomized 1:1 to receive nitazoxanide (500 mg) or placebo, 3 times daily, for 5 days, and were followed for 14 days. The primary outcome was intensive care unit admission due to the need for invasive mechanical ventilation. Secondary outcomes included clinical improvement, hospital discharge, oxygen requirements, death, and adverse events within 14 days. Results: Of the 498 patients, 405 (202 in the nitazoxanide group and 203 in the placebo group) were included in the analyses. Admission to the intensive care unit did not differ between the groups (hazard ratio [95% confidence interval], 0.68 [0.38-1.20], p = 0.179); death rates also did not differ. Nitazoxanide improved the clinical outcome (2.75 [2.21-3.43], p < 0.0001), time to hospital discharge (1.37 [1.11-1.71], p = 0.005), and reduced oxygen requirements (0.77 [0.64-0.94], p = 0.011). C-reactive protein, D-dimer, and ferritin levels were lower in the nitazoxanide group than the placebo group on day 7. No serious adverse events were observed. Conclusions: Nitazoxanide, compared with placebo, did not prevent admission to the intensive care unit for patients hospitalized with COVID-19 pneumonia. Clinical Trial Registration: Brazilian Registry of Clinical Trials (REBEC) RBR88bs9x; ClinicalTrials.gov, NCT04561219.

7.
Genomics ; 113(6): 4109-4115, 2021 11.
Article in English | MEDLINE | ID: covidwho-1492759

ABSTRACT

Genetic variants of SARS-CoV-2 have been emerging and circulating in many places across the world. Rapid detection of these variants is essential since their dissemination can impact transmission rates, diagnostic procedures, disease severity, response to vaccines or patient management. Sanger sequencing has been used as the preferred approach for variant detection among circulating human immunodeficiency and measles virus genotypes. Using primers to amplify a fragment of the SARS-CoV-2 genome encoding part of the Spike protein, we showed that Sanger sequencing allowed us to rapidly detect the introduction and spread of three distinct SARS-CoV-2 variants in two major Brazilian cities. In both cities, after the predominance of variants closely related to the virus first identified in China, the emergence of the P.2 variant was quickly followed by the detection of the P1 variant, which became dominant in less than one month after it was first detected.


Subject(s)
COVID-19/virology , Genetic Variation , High-Throughput Nucleotide Sequencing/methods , SARS-CoV-2/genetics , Brazil/epidemiology , COVID-19/epidemiology , China , Cities , Humans , Mutation , Phylogeny , Spike Glycoprotein, Coronavirus/genetics
9.
Front Immunol ; 11: 599736, 2020.
Article in English | MEDLINE | ID: covidwho-1081614

ABSTRACT

In the last few months, the coronavirus disease 2019 (COVID-19) pandemic has affected millions of people worldwide and has provoked an exceptional effort from the scientific community to understand the disease. Clinical evidence suggests that severe COVID-19 is associated with both dysregulation of damage tolerance caused by pulmonary immunopathology and high viral load. In this review article, we describe and discuss clinical studies that show advances in the understanding of mild and severe illness and we highlight major points that are critical for improving the comprehension of different clinical outcomes. The understanding of pulmonary immunopathology will contribute to the identification of biomarkers in an attempt to classify mild, moderate, severe and critical COVID-19 illness. The interface of pulmonary immunopathology and the identification of biomarkers are critical for the development of new therapeutic strategies aimed to reduce the systemic and pulmonary hyperinflammation in severe COVID-19.


Subject(s)
Biomarkers/analysis , COVID-19/immunology , COVID-19/pathology , Lung/immunology , Lung/pathology , Humans , Lung/virology , SARS-CoV-2
10.
Eur Respir J ; 58(1)2021 07.
Article in English | MEDLINE | ID: covidwho-999707

ABSTRACT

BACKGROUND: Nitazoxanide is widely available and exerts broad-spectrum antiviral activity in vitro. However, there is no evidence of its impact on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. METHODS: In a multicentre, randomised, double-blind, placebo-controlled trial, adult patients presenting up to 3 days after onset of coronavirus disease 2019 (COVID-19) symptoms (dry cough, fever and/or fatigue) were enrolled. After confirmation of SARS-CoV-2 infection using reverse transcriptase PCR on a nasopharyngeal swab, patients were randomised 1:1 to receive either nitazoxanide (500 mg) or placebo, three times daily, for 5 days. The primary outcome was complete resolution of symptoms. Secondary outcomes were viral load, laboratory tests, serum biomarkers of inflammation and hospitalisation rate. Adverse events were also assessed. RESULTS: From June 8 to August 20, 2020, 1575 patients were screened. Of these, 392 (198 placebo, 194 nitazoxanide) were analysed. Median (interquartile range) time from symptom onset to first dose of study drug was 5 (4-5) days. At the 5-day study visit, symptom resolution did not differ between the nitazoxanide and placebo arms. Swabs collected were negative for SARS-CoV-2 in 29.9% of patients in the nitazoxanide arm versus 18.2% in the placebo arm (p=0.009). Viral load was reduced after nitazoxanide compared to placebo (p=0.006). The percentage viral load reduction from onset to end of therapy was higher with nitazoxanide (55%) than placebo (45%) (p=0.013). Other secondary outcomes were not significantly different. No serious adverse events were observed. CONCLUSIONS: In patients with mild COVID-19, symptom resolution did not differ between nitazoxanide and placebo groups after 5 days of therapy. However, early nitazoxanide therapy was safe and reduced viral load significantly.


Subject(s)
COVID-19 , Adult , Humans , Nitro Compounds , SARS-CoV-2 , Thiazoles , Treatment Outcome
11.
Rev. Assoc. Med. Bras. (1992) ; 66(3):338-344, 2020.
Article in English | LILACS (Americas) | ID: grc-742959

ABSTRACT

SUMMARY The first confirmed case of coronavirus disease 2019 (COVID-19) in Brasil was reported on February 25th, 2020, and by April 3rd, 8076 were confirmed in the country. As COVID-19 disease incidence escalates in Brasil, management of cancer patients requires immediate action and oncology clinics are urged to establish a contingency plan. We have installed a COVID-19 Management Committee to elaborate and implement best practices to assist cancer outpatients as well as to provide a safe environment for clinical staff and other employees at the outpatient clinics. The challenges of cancer treatment in the midst of COVID-19 global pandemic highlight the importance of a rapid response by institutions, where organizational structure, strategic planning, agility in guidelines implementation and alternative ways to protect and support clinical staff, employees and patients may be the key to mitigate pandemic effects. RESUMO O primeiro caso confirmado de Doença Associada ao Coronavírus 2019 (COVID-19) no Brasil foi confirmado em 25 de fevereiro de 2020 e em 3 de abril já haviam 8076 casos confirmados no país. A medida que a incidência de COVID-19 aumenta no Brasil, o tratamento de pacientes com câncer exige ação imediata e as clínicas oncológicas são instadas a estabelecer um plano de contingência. Instalamos um Comitê de Manejo de COVID-19 para elaborar e implementar as melhores práticas para ajudar pacientes ambulatoriais com câncer, bem como proporcionar um ambiente seguro para a equipe clínica e outros funcionários das clínicas ambulatoriais. Os desafios do tratamento do câncer em meio à pandemia global do COVID-19 destacam a importância de uma resposta rápida das instituições, onde a estrutura organizacional, o planejamento estratégico, a agilidade na implementação de diretrizes e formas alternativas de proteger e apoiar a equipe clínica, funcionários e pacientes podem ser a chave para mitigar os efeitos da pandemia.

13.
Rev Assoc Med Bras (1992) ; 66(3): 338-344, 2020 Mar.
Article in English | MEDLINE | ID: covidwho-595462

ABSTRACT

The first confirmed case of coronavirus disease 2019 (COVID-19) in Brasil was reported on February 25th, 2020, and by April 3rd, 8076 were confirmed in the country. As COVID-19 disease incidence escalates in Brasil, management of cancer patients requires immediate action and oncology clinics are urged to establish a contingency plan. We have installed a COVID-19 Management Committee to elaborate and implement best practices to assist cancer outpatients as well as to provide a safe environment for clinical staff and other employees at the outpatient clinics. The challenges of cancer treatment in the midst of COVID-19 global pandemic highlight the importance of a rapid response by institutions, where organizational structure, strategic planning, agility in guidelines implementation and alternative ways to protect and support clinical staff, employees and patients may be the key to mitigate pandemic effects.


Subject(s)
Betacoronavirus , Coronavirus Infections/prevention & control , Medical Oncology/standards , Neoplasms/therapy , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Brazil , COVID-19 , Humans , Medical Oncology/methods , Medical Oncology/organization & administration , Risk Management , SARS-CoV-2
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