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1.
Pathogens ; 13(6)2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38921767

RESUMEN

Oropouche orthobunyavirus (OROV) is an arbovirus transmitted by midges that has been involved in outbreaks throughout Central and South America. In Brazil, human cases have been historically concentrated in the northern region of the country. Oropouche fever in humans range from mild clinical signs to rare neurological events, and is considered a neglected tropical disease in Brazil. Due to the clinical similarities to other arboviruses, such as chikungunya and dengue viruses, OROV infections are likely to be underreported. Chikungunya virus (CHIKV) cases in Brazil were first recognized in 2014 in the states of Amapá and Bahia in the north and northeast regions, respectively. Both OROV and CHIKV cause nonspecific symptoms, making clinical diagnosis difficult in a scenario of arbovirus cocirculation. Aiming to investigate OROV transmission during the CHIKV introduction in the state of Amapá located in the Brazilian Amazon, we conducted a retrospective molecular (RT-qPCR) and serological investigation in febrile cases (N = 166) collected between August 2014 and May 2015. All acute serum samples were negative for OROV RNA using RT-qPCR. However, neutralizing antibodies for OROV were detected using a plaque reduction neutralization test (PRNT90) in 10.24% (17/166) of the patients, with neutralizing antibody titers ranging from 20 to ≥640, suggesting the previous exposure of patients to OROV. Regarding CHIKV, recent exposure was confirmed by the detection of CHIKV RNA in 20.25% (33/163) of the patients and by the detection of anti-CHIKV IgM in 28.57% (44/154) of the patients. The additional detection of anti-CHIKV IgG in 12.58% (19/151) of the febrile patients suggests that some individuals had been previously exposed to CHIKV. Whether the OROV exposure reported here occurred prior or during the CHIKV circulation in Amapá, is unknown, but because those arboviral infections share similar clinical signs and symptoms, a silent circulation of enzootic arboviruses during the introduction of exotic arboviruses may occur, and highlights the importance of syndromic cases' surveillance to arboviruses in Brazil.

2.
One Health Outlook ; 6(1): 12, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38946009

RESUMEN

Oropouche and Mayaro viruses are enzootic arboviruses of public health concern throughout Latin America. Recent outbreaks of OROV in northern region and sporadic autochthonous cases in western region of Brazil, suggest a silent circulation of these neglected viruses. Aiming to investigate the exposure of different species of domestic animals to MAYV and OROV in urban and peri-urban areas of West-Central Brazil, we performed a cross-sectional serosurvey by plaque reduction neutralization test (PRNT). Our findings included neutralizing antibodies for both arboviruses in cattle, dogs and horses, suggesting eventual role of domestic animals in enzootic arbovirus surveillance in Brazil.

3.
Microorganisms ; 12(4)2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38674664

RESUMEN

The SARS-CoV-2 P.1 variant, responsible for an outbreak in Manaus, Brazil, is distinguished by 12 amino acid differences in the S protein, potentially increasing its ACE-2 affinity and immune evasion capability. We investigated the innate immune response of this variant compared to the original B.1 strain, particularly concerning cytokine production. Blood samples from three severe COVID-19 patients were analyzed post-infection with both strains. Results showed no significant difference in cytokine production of mononuclear cells and neutrophils for either variant. While B.1 had higher cytopathogenicity, neither showed viral replication in mononuclear cells. Structural analyses of the S protein highlighted physicochemical variations, which might be linked to the differences in infectivity between the strains. Our studies point to the increased infectivity of P.1 could stem from altered immunogenicity and receptor-binding affinity.

4.
Microorganisms ; 12(3)2024 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-38543645

RESUMEN

Following the first report of zika virus in March 2015, Brazil experienced its largest sylvatic yellow fever outbreak between 2016 and 2019. This study aimed to investigate the circulation of yellow fever virus (YFV) in non-human primates (NHPs) and mosquitoes collected in urban parks and other metropolitan areas of midwest Brazil between 2017 and 2018. Whole blood samples from 80 NHPs, including 48 black-tailed marmosets (Mico melanurus) and 2332 mosquitoes from six different genera, were collected in the states of Mato Grosso (MT) and Mato Grosso do Sul (MS) and then tested for YFV by RT-qPCR. Additionally, 23 plasma samples of NHPs were tested for neutralizing antibodies for YFV by a plaque reduction neutralization test (PRNT). No YFV RNA or neutralizing antibodies for YFV were detected in NHPs and mosquitoes from MT and MS. The continuous monitoring of YFV circulation in different species of NHPs and vectors in urban areas is instrumental to quickly assess potentially unknown maintenance cycles of yellow fever at the human-animal interface in Brazil.

5.
Braz J Infect Dis ; 28(1): 103706, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38081327

RESUMEN

This study compares the effects of virus-cell interactions among SARS-CoV-2 variants of concern (VOCs) isolated in Brazil in 2021, hypothesizing a correlation between cellular alterations and mortality and between viral load and transmissibility. For this purpose, reference isolates of Alpha, Gamma, Zeta, and Delta variants were inoculated into monolayers of Vero-E6 cells. Viral RNA was quantified in cell supernatants by RT‒PCR, and infected cells were analyzed by Transmission Electron Microscopy (TEM) for qualitative and quantitative evaluation of cellular changes 24, 48, and 72 hours postinfection (hpi). Ultrastructural analyses showed that all variants of SARS-CoV-2 altered the structure and function of mitochondria, nucleus, and rough endoplasmic reticulum of cells. Monolayers infected with the Delta variant showed the highest number of modified cells and the greatest statistically significant differences compared to those of other variants. Viral particles were observed in the cytosol and the cell membrane in 100 % of the cells at 48 hpi. Alpha showed the highest mean particle diameter (79 nm), and Gamma and Delta were the smallest (75 nm). Alpha and Gamma had the highest particle frequency per field at 48 hpi, while the same was observed for Zeta and Delta at 72 hpi and 24 hpi, respectively. The cycle threshold of viral RNA varied among the target protein, VOC, and time of infection. The findings presented here demonstrate that all four VOCs evaluated caused ultrastructural changes in Vero-E6 cells, which were more prominent when infection occured with the Delta variant.


Asunto(s)
COVID-19 , Citología , Humanos , SARS-CoV-2 , ARN Viral/genética
6.
Braz. j. infect. dis ; 28(1): 103706, 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1550139

RESUMEN

Abstract This study compares the effects of virus-cell interactions among SARS-CoV-2 variants of concern (VOCs) isolated in Brazil in 2021, hypothesizing a correlation between cellular alterations and mortality and between viral load and transmissibility. For this purpose, reference isolates of Alpha, Gamma, Zeta, and Delta variants were inoculated into monolayers of Vero-E6 cells. Viral RNA was quantified in cell supernatants by RT‒PCR, and infected cells were analyzed by Transmission Electron Microscopy (TEM) for qualitative and quantitative evaluation of cellular changes 24, 48, and 72 hours postinfection (hpi). Ultrastructural analyses showed that all variants of SARS-CoV-2 altered the structure and function of mitochondria, nucleus, and rough endoplasmic reticulum of cells. Monolayers infected with the Delta variant showed the highest number of modified cells and the greatest statistically significant differences compared to those of other variants. Viral particles were observed in the cytosol and the cell membrane in 100 % of the cells at 48 hpi. Alpha showed the highest mean particle diameter (79 nm), and Gamma and Delta were the smallest (75 nm). Alpha and Gamma had the highest particle frequency per field at 48 hpi, while the same was observed for Zeta and Delta at 72 hpi and 24 hpi, respectively. The cycle threshold of viral RNA varied among the target protein, VOC, and time of infection. The findings presented here demonstrate that all four VOCs evaluated caused ultrastructural changes in Vero-E6 cells, which were more prominent when infection occured with the Delta variant.

7.
Saúde debate ; 48(140): e8759, 2024. tab, graf
Artículo en Portugués | LILACS-Express | LILACS | ID: biblio-1560522

RESUMEN

RESUMO O projeto 'Saúde Única no Pantanal: participação da sociedade na vigilância de emergência de zoonoses como efeito pós-incêndios no território e formação de estratégias integradas' objetivou integrar representações institucionais e da sociedade local; ampliar o uso do Sistema de Informação em Saúde Silvestre (SISS-Geo) para o monitoramento da fauna; identificar áreas prioritárias para vigilância de zoonoses e construir caminhos envolvendo a Saúde Única (SU). Realizou webinário, apontando a necessidade de eventos mais amplos com a participação de lideranças em cada um dos territórios escolhidos. Foram executados seminários e oficinas nos estados de Mato Grosso do Sul (MS), com a participação de gestores do serviço de saúde da Província de Santa Cruz, Bolívia, e de Mato Grosso. A representatividade dos diferentes segmentos nos eventos possibilitou a articulação de cidadãos e gestores locais. Nas comunidades tradicionais, foi possível abordar os impactos dos incêndios e dar oportunidade para que essas pessoas manifestassem suas prioridades e demandas de saúde, antes e depois dos incêndios. A Oficina Síntese realizada em Corumbá, MS possibilitou a devolutiva dos resultados e a integração com representantes de diferentes instituições do Brasil e da Bolívia, além da prospecção e priorização de enfermidades a serem incorporadas em modelo de SU para o Pantanal e fronteira oeste do Brasil.


ABSTRACT The project 'One Health in the Pantanal: society's participation in the emergency surveillance of zoonoses emergency as a post-fire effect in the territory and the formation of integrated strategies' aimed to integrate institutional representations and local society; expand the use of Wildlife Health Information System (SISS-Geo) for fauna monitoring; identify priority areas for zoonosis surveillance and build paths involving One Health (OH). A webinar was held, highlighting the need for broader events with the participation of leaders in each of the chosen territories. Seminars and workshops were held in the states of Mato Grosso do Sul (MS), with the participation of health service managers from the Province of Santa Cruz, Bolivia, and Mato Grosso. The representation of different segments at the events enabled the articulation of citizens and local managers. In traditional communities, it was possible to address the impacts of the fires and provide the opportunity for these people to express their health priorities and demands, before and after the fires. The Synthesis Workshop held in Corumbá, MS allowed the feedback of results and integration with representatives from different institutions in Brazil and Bolivia, and prospecting and prioritization of illnesses to be incorporated into the OH model for the Pantanal and western border of Brazil.

8.
Front Pediatr ; 11: 1250059, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38155740

RESUMEN

Background: Vaccination schedules, as well as their effectiveness and contraindications, need to be evaluated regularly, especially in specific situations. Congenital Zika Syndrome (CZS) is a severe condition that results in extensive functional and neurological impairment of fetuses and newborns due to Zika virus tropism for fetal neural progenitor cells. Down Syndrome (DS) is the leading genetic cause of intellectual disability. The immune impairment in DS has already been described, but little is known about the immune response of CZS children. Thus, CZS and DS are specific conditions that can be considered for a reassessment of the available immunizations. Here, we carried out serological analyses of attenuated vaccines-induced antibodies for measles, rubella, and yellow fever viruses in children aged 2-7, grouped into asymptomatic controls, DS children, and CZS children. Methods: Plasma samples were taken, and vaccination records were compiled during clinical follow-up. Enzymatic immunoassays for quantifying anti-measles and anti-rubella IgG were performed to assess the response to the Measles, Mumps, and Rubella (MMR) vaccine. Plaque Reduction Neutralization Test (PRNT) was performed to investigate neutralizing antibodies in response to the Brazilian vaccine strain of yellow fever (YF-17DD). Results: We highlight similar levels of anti-measles IgG and neutralizing antibodies for YF-17DD among CZS, DS, and asymptomatic children, although low positivity of measles data was seen in the three groups. In DS children, the 2-4-year-old group had an increased level of anti-measles IgG compared to the older group of children aged five to seven years. Lower anti-rubella IgG levels were observed in CZS and DS children compared to asymptomatic children. For anti-rubella IgG, the good performance of vaccination in asymptomatic children is due to younger ones rather than older ones. Conclusions: There were no reports of adverse events after the use of the MMR and YF-17DD indicating that CZS and DS could continue to receive these vaccines, but our data draws attention to the necessity of monitoring the vaccination response in CZS and DS children over time and the possible need to adhere to national measles vaccination campaigns. Scientific research needs to continue to help develop appropriate CZS and DS health guidelines.

9.
Pharmaceutics ; 15(7)2023 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-37514075

RESUMEN

Earlier studies with montelukast (M) and telmisartan (T) have revealed their potential antiviral properties against SARS-CoV-2 wild-type (WT) but have not assessed their efficacy against emerging Variants of Concern (VOCs) such as Omicron. Our research fills this gap by investigating these drugs' impact on VOCs, a topic that current scientific literature has largely overlooked. We employed computational methodologies, including molecular mechanics and machine learning tools, to identify drugs that could potentially disrupt the SARS-CoV-2 spike RBD-ACE2 protein interaction. This led to the identification of two FDA-approved small molecule drugs, M and T, conventionally used for treating asthma and hypertension, respectively. Our study presents an additional potential use for these drugs as antivirals. Our results show that both M and T can inhibit not only the WT SARS-CoV-2 but also, in the case of M, the Omicron variant, without reaching cytotoxic concentrations. This novel finding fills an existing gap in the literature and introduces the possibility of repurposing these drugs for SARS-CoV-2 VOCs, an essential step in responding to the evolving global pandemic.

10.
BMC Infect Dis ; 23(1): 295, 2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37147601

RESUMEN

BACKGROUND: While nasopharyngeal (NP) swabs are considered the gold standard for severe acute respiratory coronavirus 2 (SARS-CoV-2) real-time reverse transcriptase-polymerase chain reaction (RT-PCR) detection, several studies have shown that saliva is an alternative specimen for COVID-19 diagnosis and screening. METHODS: To analyze the utility of saliva for the diagnosis of COVID-19 during the circulation of the Omicron variant, participants were enrolled in an ongoing cohort designed to assess the natural history of SARS-CoV-2 infection in adults and children. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and Cohen's kappa coefficient were calculated to assess diagnostic performance. RESULTS: Overall, 818 samples were collected from 365 outpatients from January 3 to February 2, 2022. The median age was 32.8 years (range: 3-94 years). RT-PCR for SARS-CoV-2 was confirmed in 97/121 symptomatic patients (80.2%) and 62/244 (25.4%) asymptomatic patients. Substantial agreement between saliva and combined nasopharyngeal/oropharyngeal samples was observed with a Cohen's kappa value of 0.74 [95% confidence interval (CI): 0.67-0.81]. Sensitivity was 77% (95% CI: 70.9-82.2), specificity 95% (95% CI: 91.9-97), PPV 89.8% (95% CI: 83.1-94.4), NPV 87.9% (95% CI: 83.6-91.5), and accuracy 88.5% (95% CI: 85.0-91.4). Sensitivity was higher among samples collected from symptomatic children aged three years and older and adolescents [84% (95% CI: 70.5-92)] with a Cohen's kappa value of 0.63 (95% CI: 0.35-0.91). CONCLUSIONS: Saliva is a reliable fluid for detecting SARS-CoV-2, especially in symptomatic children and adolescents during the circulation of the Omicron variant.


Asunto(s)
COVID-19 , Pacientes Ambulatorios , Adolescente , Adulto , Niño , Humanos , Saliva , Prueba de COVID-19 , SARS-CoV-2/genética , COVID-19/diagnóstico , Nasofaringe , Manejo de Especímenes
11.
Sci Rep ; 13(1): 7306, 2023 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-37147348

RESUMEN

The rapid spread of the SARS-CoV-2 Variant of Concern (VOC) Gamma in Amazonas during early 2021 fueled a second large COVID-19 epidemic wave and raised concern about the potential role of reinfections. Very few cases of reinfection associated with the VOC Gamma have been reported to date, and their potential impact on clinical, immunological, and virological parameters remains largely unexplored. Here we describe 25 cases of SARS-CoV-2 reinfection in Brazil. SARS-CoV-2 genomic analysis confirmed that individuals were primo-infected with distinct viral lineages between March and December 2020 (B.1.1, B.1.1.28, B.1.1.33, B.1.195, and P.2) and reinfected with the VOC Gamma between 3 to 12 months after primo-infection. We found a similar mean cycle threshold (Ct) value and limited intra-host viral diversity in both primo-infection and reinfection samples. Sera of 14 patients tested 10-75 days after reinfection displayed detectable neutralizing antibodies (NAb) titers against SARS-CoV-2 variants that circulated before (B.1.*), during (Gamma), and after (Delta and Omicron) the second epidemic wave in Brazil. All individuals had milder or no symptoms after reinfection, and none required hospitalization. These findings demonstrate that individuals reinfected with the VOC Gamma may display relatively high RNA viral loads at the upper respiratory tract after reinfection, thus contributing to onward viral transmissions. Despite this, our study points to a low overall risk of severe Gamma reinfections, supporting that the abrupt increase in hospital admissions and deaths observed in Amazonas and other Brazilian states during the Gamma wave was mostly driven by primary infections. Our findings also indicate that most individuals analyzed developed a high anti-SARS-CoV-2 NAb response after reinfection that may provide some protection against reinfection or disease by different SARS-CoV-2 variants.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Brasil/epidemiología , COVID-19/epidemiología , Diversidad de Anticuerpos , Rayos gamma , Reinfección , Gravedad del Paciente
12.
PLoS One ; 17(11): e0277612, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36395285

RESUMEN

Mayaro virus (MAYV, Togaviridae) and Oropouche orthobunyavirus (OROV, Peribunyaviridae) are emerging enzootic arboviruses in Latin America. Outbreaks of febrile illness associated with MAYV and OROV have been reported among humans mainly in the northern region of Brazil since the 1980s, and recent data suggest these viruses have circulated also in more populated areas of western Brazil. MAYV shares mosquito vectors with yellow fever virus and it has been historically detected during yellow fever epidemics. Aiming to investigate the transmission of OROV and MAYV at the human-animal interface during a yellow fever, chikungunya and Zika outbreaks in Brazil, we conducted a retrospective molecular investigation in 810 wild and domestic animals, 106 febrile patients, and 22.931 vectors collected from 2016 to 2018 in Cuiaba and Campo Grande metropolitan regions, western Brazil. All samples tested negative for OROV and MAYV RNA by RT-qPCR. Findings presented here suggest no active circulation of MAYV and OROV in the sampled hosts. Active surveillance and retrospective investigations are instrumental approaches for the detection of cryptic and subclinical activity of enzootic arboviruses and together serve as a warning system to implement appropriate actions to prevent outbreaks.


Asunto(s)
Arbovirus , Orthobunyavirus , Fiebre Amarilla , Infección por el Virus Zika , Virus Zika , Animales , Humanos , Brasil/epidemiología , Estudios Retrospectivos , Orthobunyavirus/genética , Arbovirus/genética
13.
Viruses ; 14(11)2022 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-36366557

RESUMEN

Infections with arboviruses are reported worldwide. Saint Louis encephalitis (SLEV) and West Nile (WNV) viruses are closely related flaviviruses affecting humans and animals. SLEV has been sporadically detected in humans, and corresponding antibodies have been frequently detected in horses throughout Brazil. WNV was first reported in western Brazil over a decade ago, has been associated with neurological disorders in humans and equines and its prevalence is increasing nationwide. Herein, we investigated by molecular and serological methods the presence of SLEV and WNV in equines from Rio de Janeiro. A total of 435 serum samples were collected from healthy horses and tested for specific neutralizing antibodies by plaque reduction neutralization test (PRNT90). Additionally, samples (serum, cerebrospinal fluid, central nervous system tissue) from 72 horses, including horses with neurological disorders resulting in a fatal outcome or horses which had contact with them, were tested by real-time reverse transcription-polymerase chain reaction (RT-qPCR) for both viruses. Adopting the criterion of four-fold antibody titer difference, 165 horses (38%) presented neutralizing antibodies for flaviviruses, 89 (20.4%) for SLEV and five (1.1%) for WNV. No evidence of SLEV and WNV infection was detected by RT-qPCR and, thus, such infection could not be confirmed in the additional samples. Our findings indicate horses of Rio de Janeiro were exposed to SLEV and WNV, contributing to the current knowledge on the distribution of these viruses in Brazil.


Asunto(s)
Encefalitis de San Luis , Flavivirus , Enfermedades de los Caballos , Fiebre del Nilo Occidental , Virus del Nilo Occidental , Animales , Humanos , Caballos , Virus del Nilo Occidental/genética , Encefalitis de San Luis/epidemiología , Encefalitis de San Luis/veterinaria , Brasil/epidemiología , Anticuerpos Antivirales , Fiebre del Nilo Occidental/epidemiología , Fiebre del Nilo Occidental/veterinaria , Anticuerpos Neutralizantes , Enfermedades de los Caballos/epidemiología
14.
Biol Methods Protoc ; 7(1): bpac021, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36128169

RESUMEN

Serum samples of 20 hospitalized coronavirus disease 2019 (COVID-19) patients from Brazil who were infected by the earlier severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lineages B.1.1.28 and B.1.1.33, and by the variant of concern (VOC) Gamma (P.1) were tested by plaque reduction neutralization test (PRNT90) with wild isolates of a panel of SARS-CoV-2 lineages, including B.1, Zeta, N.10, and the VOCs Gamma, Alpha, and Delta that emerged in different timeframes of the pandemic. The main objective of this study was to evaluate if the serum of patients infected by earlier lineages was capable to neutralize later emerged VOCs. We also evaluated if the 4-fold difference in PRNT90 titers is a reliable seropositivity criterion to distinguish infections caused by different SARS-CoV-2 lineages. Sera collected between May 2020 and August 2021 from the day of admittance to the hospital to 21 days after diagnostic of patients infected by the two earlier lineages B.1.1.28 and B.1.1.33 presented neutralizing capacity for all challenged VOCs, including Gamma and Delta. Among all variants tested, Delta and N.10 presented the lowest geometric mean of neutralizing antibody titers, and B.1.1.7, presented the highest titers. Four patients infected with Gamma, that emerged in December 2020, presented neutralizing antibodies for B.1, B.1.1.33, and B.1.1.28, its ancestor lineage. All of them had neutralizing antibodies under the level of detection for the VOC Delta. Patients infected by B.1.1.28 presented very similar geometric mean of neutralizing antibody titers for both B.1.1.33 and B.1.1.28. Findings presented here indicate that most patients infected in early stages of COVID-19 pandemic presented neutralizing antibodies capable to neutralize wild types of all later emerged VOCs in Brazil, and that the 4-fold difference in PRNT90 titers is not reliable to distinguish humoral response among different SARS-CoV-2 lineages.

15.
Emerg Microbes Infect ; 11(1): 2112-2115, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35950943

RESUMEN

After identifying a captive herd of white-tailed deer in central Texas with >94% seroprevalence with SARS-CoV-2 neutralizing antibodies in September 2021, we worked retrospectively through archived serum samples of 21 deer and detected seroconversion of all animals between December 2020 and January 2021. We then collected prospective samples to conclude that the duration of persistence of neutralizing antibodies is at least 13 months for 19 (90.5%) of the animals, with two animals converting to seronegative after six and eight months. Antibody titres generally waned over this time frame, but three deer had a temporary 4- to 8-fold increases in plaque reduction neutralization test titres over a month after seroconversion; anamnestic response cannot be ruled out.


Asunto(s)
COVID-19 , Ciervos , Animales , Anticuerpos Neutralizantes , COVID-19/veterinaria , Estudios Prospectivos , Estudios Retrospectivos , SARS-CoV-2 , Estudios Seroepidemiológicos , Texas/epidemiología
16.
Sci Rep ; 12(1): 11500, 2022 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-35798777

RESUMEN

Despite the advance of vaccination worldwide, epidemic waves caused by more transmissible and immune evasive genetic variants of SARS-CoV-2 have sustained the ongoing pandemic of COVID-19. Monitoring such variants is expensive, as it usually relies on whole-genome sequencing methods. Therefore, it is necessary to develop alternatives that could help identify samples from specific variants. Reverse transcription loop-mediated isothermal amplification is a method that has been increasingly used for nucleic acid amplification, as it is cheaper and easier to perform when compared to other molecular techniques. As a proof of concept that can help distinguish variants, we present an RT-LAMP assay capable of detecting samples carrying a group of mutations that can be related to specific SARS-CoV-2 lineages, here demonstrated for the Variant of Concern Gamma. We tested 60 SARS-CoV-2 RNA samples extracted from swab samples and the reaction showed a sensitivity of 93.33%, a specificity of 88.89% and a kappa value of 0.822 for samples with a Ct ≤ 22.93. The RT-LAMP assay demonstrated to be useful to distinguish VOC Gamma and may be of particular interest as a screening approach for variants in countries with poor sequencing coverage.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , COVID-19/epidemiología , Colorimetría/métodos , Cartilla de ADN , Humanos , Técnicas de Diagnóstico Molecular/métodos , Mutación , Técnicas de Amplificación de Ácido Nucleico/métodos , ARN Viral/genética , SARS-CoV-2/genética , Sensibilidad y Especificidad
17.
Viruses ; 14(5)2022 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-35632729

RESUMEN

Dozens of orthobunyaviruses have been isolated in Brazil, and at least thirteen have been associated with human disease. The Oropouche virus has received most attention for having caused explosive epidemics with hundreds of thousands of cases in the north region between the 1960sand the 1980s, and since then has been sporadically detected elsewhere in the country. Despite their importance, little is known about their enzootic cycles of transmission, amplifying hosts and vectors, and biotic and abiotic factors involved in spillover events to humans. This overview aims to combine available data of neglected orthobunyaviruses of several serogroups, namely, Anopheles A, Anopheles B, Bunyamwera, California, Capim, Gamboa, Group C, Guama, Simbu and Turlock, in order to evaluate the current knowledge and identify research gaps in their natural transmission cycles in Brazil to ultimately point to the future direction in which orthobunyavirus research should be guided.


Asunto(s)
Anopheles , Orthobunyavirus , Animales , Brasil/epidemiología , Humanos , Mosquitos Vectores , Serogrupo
18.
J Med Entomol ; 59(4): 1479-1483, 2022 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-35640635

RESUMEN

Flies and other arthropods mechanically transmit multiple pathogens and a recent experimental study demonstrated house flies, Musca domestica L. (Diptera: Muscidae), can mechanically transmit SARS-CoV-2. The purpose of this study was to explore the possibility of mechanical transmission of SARS-CoV-2 by domestic insects and their potential as a xenosurveillance tool for detection of the virus. Flies were trapped in homes where at least one confirmed human COVID-19 case(s) resided using sticky and liquid-baited fly traps placed inside and outside the home in the Texas counties of Brazos, Bell, and Montgomery, from June to September 2020. Flies from sticky traps were identified, pooled by taxa, homogenized, and tested for the presence of SARS-CoV-2 RNA using quantitative reverse transcription PCR (RT-qPCR). Liquid traps were drained, and the collected fluid similarly tested after RNA concentration. We processed the contents of 133 insect traps from 40 homes, which contained over 1,345 individual insects of 11 different Diptera families and Blattodea. These individuals were grouped into 243 pools, and all tested negative for SARS-CoV-2 RNA. Fourteen traps in seven homes were deployed on the day that cat or dog samples tested positive for SARS-CoV-2 RNA by nasal, oral, body, or rectal samples. This study presents evidence that biting and nonbiting flies and cockroaches (Blattodea) are not likely to contribute to mechanical transmission of SARS-CoV-2 or be useful in xenosurveillance for SARS-CoV-2.


Asunto(s)
COVID-19 , Cucarachas , Enfermedades de los Perros , Moscas Domésticas , Muscidae , Animales , Perros , Humanos , Control de Insectos , ARN Viral , SARS-CoV-2
20.
Front Med (Lausanne) ; 9: 839389, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35308526

RESUMEN

The present study investigated a SARS-CoV-2 infection in placenta and fetal samples from an early pregnancy miscarriage in Midwest Brazil. The Gamma variant was isolated and fully sequenced from the placenta sample, but not from fetal samples. Our findings highlight potential adverse perinatal outcomes caused by SARS-CoV-2 Gamma infection during pregnancy.

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