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1.
Viruses ; 15(2)2023 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-36851541

RESUMO

São Paulo is the financial center of Brazil, with a population of over 12 million, that receives travelers from all over the world for business and tourism. It was the first city in Brazil to report a case of COVID-19 that rapidly spread across the city despite the implementation of the restriction measures. Despite many reports, much is still unknown regarding the genomic diversity and transmission dynamics of this virus in the city of São Paulo. Thus, in this study, we provide a retrospective overview of the COVID-19 epidemic in São Paulo City, Southeastern, Brazil, by generating a total of 9995 near-complete genome sequences from all the city's different macro-regions (North, West, Central, East, South, and Southeast). Our analysis revealed that multiple independent introduction events of different variants (mainly Gamma, Delta, and Omicron) occurred throughout time. Additionally, our estimates of viral movement within the different macro-regions further suggested that the East and the Southeast regions were the largest contributors to the Gamma and Delta viral exchanges to other regions. Meanwhile, the North region had a higher contribution to the dispersion of the Omicron variant. Together, our results reinforce the importance of increasing SARS-CoV-2 genomic monitoring within the city and the country to track the real-time evolution of the virus and to detect earlier any eventual emergency of new variants of concern that could undermine the fight against COVID-19 in Brazil and worldwide.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , SARS-CoV-2/genética , Brasil/epidemiologia , América Latina , Estudos Retrospectivos
2.
BMC Public Health ; 23(1): 15, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36597102

RESUMO

BACKGROUND: Brazil has been dramatically hit by the SARS-CoV-2 pandemic and is a world leader in COVID-19 morbidity and mortality. Additionally, the largest country of Latin America has been a continuous source of SARS-CoV-2 variants and shows extraordinary variability of the pandemic strains probably related to the country´s outstanding position as a Latin American economical and transportation hub. Not all regions of the country show sufficient infrastructure for SARS-CoV-2 diagnosis and genotyping which can negatively impact the pandemic response. METHODS: Due to this reason and to disburden the diagnostic system of the inner São Paulo State, the Butantan Institute established the Mobile Laboratory (in Portuguese: LabMovel) for SARS-CoV-2 testing which started a trip of the most important "hotspots" of the most populous Brazilian region. The LabMovel initiated in two important cities of the State: Aparecida do Norte (an important religious center) and the Baixada Santista region which incorporates the port of Santos, the busiest in Latin America. The LabMovel was fully equipped with an automatized system for SARS-CoV-2 diagnosis and sequencing/genotyping. It also integrated the laboratory systems for patient records and results divulgation including in the Federal Brazilian Healthcare System. RESULTS: Currently,16,678 samples were tested, among them 1,217 from Aparecida and 4,564 from Baixada Santista. We tracked the delta introductio in the tested regions with its high diversification. The established mobile SARS-CoV-2 laboratory had a major impact on the Public Health System of the included cities including timely delivery of the results to the healthcare agents and the Federal Healthcare system, evaluation of the vaccination status of the positive individuals in the background of exponential vaccination process in Brazil and scientific and technological divulgation of the fieldwork to the most vulnerable populations. CONCLUSIONS: The SARS-CoV-2 pandemic has demonstrated worldwide the importance of science to fight against this viral agent and the LabMovel shows that it is possible to integrate researchers, clinicians, healthcare workers and patients to take rapid actions that can in fact mitigate this and other epidemiological situations.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , COVID-19/epidemiologia , Teste para COVID-19 , Brasil/epidemiologia , Pandemias/prevenção & controle , Populações Vulneráveis
3.
Viruses ; 14(9)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36146888

RESUMO

The authors hereby request the inclusion of two authors (Olivia Teixeira and Maria Cristina Nonato) in the recently published article in Viruses entitled "Nucleocapsid (N) gene mutations of SARS-CoV-2 can affect real-time RT-PCR diagnostic and impact false-negative results" [...].

4.
Nat Microbiol ; 7(9): 1490-1500, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35982313

RESUMO

The high numbers of COVID-19 cases and deaths in Brazil have made Latin America an epicentre of the pandemic. SARS-CoV-2 established sustained transmission in Brazil early in the pandemic, but important gaps remain in our understanding of virus transmission dynamics at a national scale. We use 17,135 near-complete genomes sampled from 27 Brazilian states and bordering country Paraguay. From March to November 2020, we detected co-circulation of multiple viral lineages that were linked to multiple importations (predominantly from Europe). After November 2020, we detected large, local transmission clusters within the country. In the absence of effective restriction measures, the epidemic progressed, and in January 2021 there was emergence and onward spread, both within and abroad, of variants of concern and variants under monitoring, including Gamma (P.1) and Zeta (P.2). We also characterized a genomic overview of the epidemic in Paraguay and detected evidence of importation of SARS-CoV-2 ancestor lineages and variants of concern from Brazil. Our findings show that genomic surveillance in Brazil enabled assessment of the real-time spread of emerging SARS-CoV-2 variants.


Assuntos
COVID-19 , SARS-CoV-2 , Brasil , Genômica , Humanos
5.
Viruses ; 14(7)2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35891460

RESUMO

Our effort in SARS-CoV-2 genomic surveillance in Brazil has detected the Alpha Variant of Concern with a predominance higher than 75% in the population of Ilhabela island (São Paulo State) at a time when the Gamma VOC was already predominating the mainland raised concerns for closer surveillance on this island. Therefore, we intensified the surveillance for 24 weeks by generating data from 34% of local positive cases. Our data show that the patterns of VOC predominance dynamics and infection rates were in general distinct from the mainland. We report here the first known case of Alpha predominance in a Brazilian population, a delay greater than 3 months for the Gamma to dominate the previous variants compared to the mainland, and a faster dispersion rate of Gamma and Delta VOCs compared to the mainland. Phylogenetic analysis revealed the SARS-CoV-2 transmission dynamics in Ilhabela were characterized by multiple independent introduction events of Gamma and Delta, with a few events of Alpha introduction, two of them followed by community transmission. This study evidenced the peculiar behavior of SARS-CoV-2 variants in an isolated population and brought to light the importance of specific programs for SARS-CoV-2 genomic surveillance in isolated populations.


Assuntos
COVID-19 , SARS-CoV-2 , Brasil/epidemiologia , COVID-19/epidemiologia , Humanos , Filogenia , SARS-CoV-2/genética
6.
medRxiv ; 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35378755

RESUMO

Brazil has experienced some of the highest numbers of COVID-19 cases and deaths globally and from May 2021 made Latin America a pandemic epicenter. Although SARS-CoV-2 established sustained transmission in Brazil early in the pandemic, important gaps remain in our understanding of virus transmission dynamics at the national scale. Here, we describe the genomic epidemiology of SARS-CoV-2 using near-full genomes sampled from 27 Brazilian states and a bordering country - Paraguay. We show that the early stage of the pandemic in Brazil was characterised by the co-circulation of multiple viral lineages, linked to multiple importations predominantly from Europe, and subsequently characterized by large local transmission clusters. As the epidemic progressed under an absence of effective restriction measures, there was a local emergence and onward international spread of Variants of Concern (VOC) and Variants Under Monitoring (VUM), including Gamma (P.1) and Zeta (P.2). In addition, we provide a preliminary genomic overview of the epidemic in Paraguay, showing evidence of importation from Brazil. These data reinforce the usefulness and need for the implementation of widespread genomic surveillance in South America as a toolkit for pandemic monitoring that provides a means to follow the real-time spread of emerging SARS-CoV-2 variants with possible implications for public health and immunization strategies.

7.
J Med Virol ; 94(7): 3394-3398, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35229308

RESUMO

Delta VOC is highly diverse with more than 120 sublineages already described as of November 30, 2021. In this study, through active monitoring of circulating severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants in the state of São Paulo, southeast Brazil, we identified two emerging sublineages from the ancestral AY.43 strain which were classified as AY.43.1 and AY.43.2. These sublineages were defined by the following characteristic nonsynonymous mutations ORF1ab:A4133V and ORF3a:T14I for the AY.43.1 and ORF1ab:G1155C for the AY.43.2 and our analysis reveals that they might have a likely-Brazilian origin. Much is still unknown regarding their dissemination in the state of São Paulo and Brazil as well as their potential impact on the ongoing vaccination process. However, the results obtained in this study reinforce the importance of genomic surveillance activity for timely identification of emerging SARS-CoV-2 variants which can impact the ongoing SARS-CoV-2 vaccination and public health policies.


Assuntos
COVID-19 , SARS-CoV-2 , Brasil/epidemiologia , COVID-19/epidemiologia , Vacinas contra COVID-19 , Genômica , Humanos , SARS-CoV-2/genética
8.
Virus Res ; 308: 198643, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34848213

RESUMO

The SARS-CoV-2 alpha VOC (also known as lineage B.1.1.7) initially described in the autumn, 2020 in UK, rapidly became the dominant lineage across much of Europe. Despite multiple studies reporting molecular evidence suggestive of its circulation in Brazil, much is still unknown about its genomic diversity in the state of São Paulo, the main Brazilian economic and transportation hub. To get more insight regarding its transmission dynamics into the State we performed phylogenetic analysis on all alpha VOC strains obtained between February and August 2021 from the Sao Paulo state Network for Pandemic Alert of Emerging SARS-CoV-2 variants. The performed phylogenetic analysis showed that most of the alpha VOC genomes were interspersed with viral strains sampled from different Brazilian states and other countries suggesting that multiple independent Alpha VOC introductions from Brazil and overseas have occurred in the São Paulo State over time. Nevertheless, large monophyletic clusters were also observed especially from the Central-West part of the São Paulo State (the city of Bauru) and the metropolitan region of the São Paulo city. Our results highlight the Alpha VOC molecular epidemiology in the São Paulo state and reinforce the need for continued genomic surveillance strategies for the real-time monitoring of potential emerging SARS-CoV-2 variants during the ever-growing vaccination process.


Assuntos
COVID-19 , Filogenia , SARS-CoV-2/genética , Brasil/epidemiologia , COVID-19/epidemiologia , COVID-19/virologia , Genômica , Humanos , Organização Mundial da Saúde
9.
Viruses ; 13(12)2021 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-34960743

RESUMO

The current COVID-19 pandemic demands massive testing by Real-time RT-PCR (Reverse Transcription Polymerase Chain Reaction), which is considered the gold standard diagnostic test for the detection of the SARS-CoV-2 virus. However, the virus continues to evolve with mutations that lead to phenotypic alterations as higher transmissibility, pathogenicity or vaccine evasion. Another big issue are mutations in the annealing sites of primers and probes of RT-PCR diagnostic kits leading to false-negative results. Therefore, here we identify mutations in the N (Nucleocapsid) gene that affects the use of the GeneFinder COVID-19 Plus RealAmp Kit. We sequenced SARS-CoV-2 genomes from 17 positive samples with no N gene detection but with RDRP (RNA-dependent RNA polymerase) and E (Envelope) genes detection, and observed a set of three different mutations affecting the N detection: a deletion of 18 nucleotides (Del28877-28894), a substitution of GGG to AAC (28881-28883) and a frameshift mutation caused by deletion (Del28877-28878). The last one cause a deletion of six AAs (amino acids) located in the central intrinsic disorder region at protein level. We also found this mutation in 99 of the 14,346 sequenced samples by the Sao Paulo state Network for Pandemic Alert of Emerging SARS-CoV-2 variants, demonstrating the circulation of the mutation in Sao Paulo, Brazil. Continuous monitoring and characterization of mutations affecting the annealing sites of primers and probes by genomic surveillance programs are necessary to maintain the effectiveness of the diagnosis of COVID-19.


Assuntos
Teste de Ácido Nucleico para COVID-19 , COVID-19/diagnóstico , Proteínas do Nucleocapsídeo de Coronavírus/genética , SARS-CoV-2/isolamento & purificação , Brasil/epidemiologia , COVID-19/epidemiologia , RNA-Polimerase RNA-Dependente de Coronavírus/genética , Primers do DNA , Reações Falso-Negativas , Genoma Viral/genética , Humanos , Mutação , Fosfoproteínas/genética , RNA Viral/genética , SARS-CoV-2/genética
10.
Res Vet Sci ; 135: 557-567, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33541712

RESUMO

The aim of this study was to evaluate if the cottonseed intake during gestation and lactation affects the ovarian population in ewes and lambs. Therefore, 39 ewes were evaluated during 10 months under two treatments: Cottonseed and soybeans. The quantification of ovarian follicular dynamics was analyzed by ultrasound and the determination of progesterone and estradiol levels was interpreted by radioimmunoassay. After weaning, ovaries of lambs (n = 10) were collected by ovariectomy and fixed for the assessment of follicular parameters as normality, classification, diameter, ultrastructure, stereology, and as well as immunoexpression of the α-estradiol receptor α (ER-α). The results showed that the cottonseed consumption altered neither the ovarian nor the hormonal follicular dynamics of Santa Inês ewes after calving and did not affect the normality, classification, diameter, stereology and follicular ultrastructure of offspring. Nevertheless, the offspring of ewes fed with cottonseed showed high ER-α immunoexpression in the ovarian structures. It is concluded that cottonseed did not affect the maternal-descendant follicular dynamics. However, lambs' ovaries had highest α-ER immunoexpression in oocytes, granulosa and theca cells and corpus luteum. This fact warns of a possible change in the future steroidogenic response of these lambs that had progenitors consuming cottonseed in their reproductive period.


Assuntos
Gossipol/farmacologia , Ovário/efeitos dos fármacos , Ovinos , Animais , Feminino , Gossipol/administração & dosagem , Lactação , Oócitos/metabolismo , Gravidez , Progesterona , Reprodução
11.
Anim Reprod Sci ; 201: 22-31, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30567637

RESUMO

Manipulation of oocytes enclosed in preantral follicles (MOEPF) allows for analyzing follicular development and use of this biotechnology in the pre-analysis of the beneficial or toxic effects of bio-products on granulosa cells and oocytes at different developmental stages. In this study, there was evaluation of the effects of gossypol by culturing granulosa cells and oocytes in ewe ovarian tissues. Ovarian tissues were cultured with gossypol at 37 °C, in humidified air and 5% CO2. Variables that were evaluated were morphology, morphometry, ultrastructure and abundance of estradiol receptor α (α-ER). There were no differences in developmental characteristics when there was treatment with any of the gossypol doses that were evaluated. Immunostaining indicated that when the gossypol dose increases, the abundance of α-ER also increases in the cytoplasm, nucleus, and granulosa cells. Findings with the ultrastructural analysis indicated that for granulosa cells there was fewer cells and greater disorganization and a lack of structural integrity of follicular cell layers as a result of all gossypol treatments. The culture of oocytes in preantral ovarian follicles in presence of gossypol did not affect the morphological-metric structure at the doses evaluated. The findings with evaluation of ultrastructural and immunohistochemical structures indicated granulosa cells and α-ER were affected by the treatments with gossypol indicating there were effects of this compound on ovarian function in sheep. This study indicated there is a toxic action of gossypol when using the biotechnology, MOEPF. Thus, gossypol negatively affects granulosa cell development and structural integrity of preantral follicles in sheep.


Assuntos
Gossipol/farmacologia , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/ultraestrutura , Oócitos/efeitos dos fármacos , Ovinos/fisiologia , Animais , Células Cultivadas , Receptor alfa de Estrogênio/efeitos dos fármacos , Receptor alfa de Estrogênio/metabolismo , Feminino , Células da Granulosa/fisiologia , Imuno-Histoquímica/veterinária , Oócitos/fisiologia , Oócitos/ultraestrutura
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