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1.
Artículo en Inglés | MEDLINE | ID: mdl-39320520

RESUMEN

BACKGROUND: Limited information exists on carriage of multidrug-resistant organisms (MDRO) by health workers (HWs) in primary care settings. This study aims to determine the prevalence of MDRO carriage among HWs in primary care and to identify associated risk factors. METHODS: A cross-sectional study was conducted across all 12 primary care units in São Caetano do Sul-SP, Brazil, from October to December 2023. Self-collected samples (nasal, oropharyngeal, and inguinal) were obtained. Environment cultures (potable water, sewage and stream water) were evaluated. Stenotrophomonas maltophilia isolates (human and environmental) were typed. RESULTS: The study included 265/288 (92%) of HWs in primary care teams, mostly women with a median age of 47 years (IQR 38-57); 78% had no comorbidities. MDRO colonisation was found in 8.7% (23 HWs). The following bacteria were found: S. maltophilia (n = 9; 3.4%) in inguinal swabs; methicillin-resistant Staphylococcus aureus (n = 8; 3%) from all sites; extended-spectrum ß-lactamase-producing bacteria (n = 5; 2%) in inguinal swabs; and vancomycin-resistant enterococci in an inguinal swab (n = 1; 0.4%). Previous antibiotic use was significantly associated with MDRO colonisation (OR 2.91, 95% CI 1.19-7.09, p = 0.018), mainly narrow spectrum oral beta-lactams and macrolides. S. malthophilia was polyclonal and human and environmental isolates differed. CONCLUSION: Colonisation by MRSA, VRE, and ESBL-producing bacteria was low; however, 4% were surprisingly colonized by polyclonal S. maltophilia. This pathogen may also suggest using narrow-spectrum rather than the expected broad-spectrum antimicrobials. Antibiotic use was the only risk factor found, mainly with oral narrow-spectrum drugs.

2.
Braz J Infect Dis ; 28(4): 103855, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39053887

RESUMEN

In Brazil, Dengue, Zika and Chikungunya viruses constitute a major threat to the public health system. Simultaneous circulation of these arboviruses occurs in many regions of the world due to the expansion of transmission vectors. The infection by these arboviruses triggers similar symptoms during their acute phase. However, in some cases, severe symptoms may occur, leading to different types of disabilities and even death. In this context, considering the similarity of the symptoms, the problems caused by the infection of these arboviruses, and the increasing risk of coinfection in humans, the differential diagnosis of these infections is essential for clinical management and epidemiological investigation. Thus, this study aimed to identify, through diagnosis via Quantitative Polymerase Chain Reaction with Reverse Transcription, arbovirus coinfection in patients from the Tocantins state (Northern Brazil). A total of 495 samples were analyzed, three from which were determined to be a coinfection of Dengue and Chikungunya viruses. The data obtained here indicate the co-circulation and coinfection by Dengue and Chikungunya viruses in the Tocantins state. These results highlight the importance of monitoring the circulation of these arboviruses for the development of health actions that aim their prevention and combat, as well as their clinical and therapeutic management.


Asunto(s)
Arbovirus , Fiebre Chikungunya , Coinfección , Dengue , Reacción en Cadena de la Polimerasa Multiplex , Humanos , Brasil/epidemiología , Fiebre Chikungunya/diagnóstico , Dengue/diagnóstico , Coinfección/virología , Arbovirus/genética , Arbovirus/aislamiento & purificación , Adulto , Femenino , Masculino , Infección por el Virus Zika/diagnóstico , Adulto Joven , Persona de Mediana Edad , Adolescente , Niño , Reacción en Cadena en Tiempo Real de la Polimerasa , Infecciones por Arbovirus/virología , Infecciones por Arbovirus/diagnóstico , Preescolar , Virus del Dengue/genética , Virus del Dengue/aislamiento & purificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Virus Chikungunya/genética , Virus Chikungunya/aislamiento & purificación
3.
Braz. j. infect. dis ; Braz. j. infect. dis;28(4): 103855, 2024. tab
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1574225

RESUMEN

ABSTRACT In Brazil, Dengue, Zika and Chikungunya viruses constitute a major threat to the public health system. Simultaneous circulation of these arboviruses occurs in many regions of the world due to the expansion of transmission vectors. The infection by these arboviruses triggers similar symptoms during their acute phase. However, in some cases, severe symptoms may occur, leading to different types of disabilities and even death. In this context, considering the similarity of the symptoms, the problems caused by the infection of these arboviruses, and the increasing risk of coinfection in humans, the differential diagnosis of these infections is essential for clinical management and epidemiological investigation. Thus, this study aimed to identify, through diagnosis via Quantitative Polymerase Chain Reaction with Reverse Transcription, arbovirus coinfection in patients from the Tocantins state (Northern Brazil). A total of 495 samples were analyzed, three from which were determined to be a coinfection of Dengue and Chikungunya viruses. The data obtained here indicate the co-circulation and coinfection by Dengue and Chikungunya viruses in the Tocantins state. These results highlight the importance of monitoring the circulation of these arboviruses for the development of health actions that aim their prevention and combat, as well as their clinical and therapeutic management.

4.
PLoS One ; 18(8): e0291027, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37651462

RESUMEN

BACKGROUND: Redondovirus (ReDoV) is a DNA virus present in the respiratory tract of many healthy individuals. Since SARS-CoV-2, the virus responsible for COVID-19, also primarily infects the same site, we evaluated whether ReDoV was present at increased frequency in patients with COVID-19 and influenced infection parameters. METHODS: Saliva samples were collected weekly from 59 individuals with COVID-19 and from 132 controls. ReDoV was detected by polymerase chain reaction and the genotypes were identified by metagenomics. Torque Teno Virus (TTV) in these samples were previously reported. RESULTS: ReDoV was detected in saliva more frequently from COVID-19 patients (72.9%) than from controls (50.0%) (p = 0.0015). There were no associations between ReDoV detection and either continuous or intermittent SARS-CoV-2 shedding, the duration of SARS-CoV-2 detection in saliva, patients' sex or if infection was by the B1 or Gamma strain. The two ReDoV strains, Brisavirus and Vientovirus, were present in equivalent frequencies in ReDoV-positive COVID-19 patients and controls. Phylogenetic analysis suggested that the two ReDoV strains in Brazil were similar to strains previously detected on other continents. CONCLUSION: ReDoV expression in saliva is increased in males and females in Brazil with mild COVID-19 but its presence does not appear to influence properties of the SARS-CoV-2 infection.


Asunto(s)
COVID-19 , SARS-CoV-2 , Femenino , Masculino , Humanos , Brasil/epidemiología , Filogenia , Saliva
5.
Biosens Bioelectron ; 239: 115614, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37607446

RESUMEN

The emergence of the graphene-based hybrid electrical-electrochemical vertical device (EEVD) has introduced a promising nanostructured biosensor tailored for point-of-care applications. In this study, we present an innovative EEVD capable of simultaneously detecting the receptor binding domain (RBD) of the SARS-CoV-2 spike protein in both serum and saliva. The foundation of the EEVD lies in a poly-neutral red-graphene heterojunction, which has been enhanced with a bioconjugate of gold nanoparticles and antibodies. The biodevice demonstrates a remarkable limit of detection, registering at the femtomolar scale (2.86 fmol L-1 or 0.1 pg mL-1). Its sensitivity is characterized by a 6.1 mV/decade response, and its operational range spans 10-12 to 10-7 g mL-1 in both serum and saliva samples. With a 20.0 µL of biological samples and a rapid processing time of under 10 min, the EEVD achieves the feat of dual antigen detection. The tests achieved 100.0% specificity, accuracy, and sensitivity in saliva, and 100.0% specificity, 88.9% accuracy, and 80.0% sensitivity in serum. This study highlights the EEVD as a low-cost solution of rapid viral detection during the crucial initial phases of COVID-19 infections.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Grafito , Nanopartículas del Metal , Humanos , SARS-CoV-2 , Saliva , COVID-19/diagnóstico , Oro
6.
Diagnostics (Basel) ; 13(13)2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37443699

RESUMEN

Chikungunya (CHIK) is a debilitating mosquito-borne disease with an epidemiology and early clinical symptoms similar to those of other arboviruses-triggered diseases such as dengue or Zika. Accurate and rapid diagnosis of CHIK virus (CHIKV) infection is therefore challenging. This international study evaluated the performance of the automated VIDAS® anti-CHIKV IgM and IgG assays compared to that of manual competitor IgM and IgG ELISA for the detection of anti-CHIKV IgM and IgG antibodies in 660 patients with suspected CHIKV infection. Positive and negative agreements of the VIDAS® CHIKV assays with ELISA ranged from 97.5% to 100.0%. The sensitivity of the VIDAS® CHIKV assays evaluated in patients with a proven CHIKV infection confirmed reported kinetics of anti-CHIKV IgM and IgG response, with a positive detection of 88.2-100.0% for IgM ≥ 5 days post symptom onset and of 100.0% for IgG ≥ 11 days post symptom onset. Our study also demonstrated the superiority of ELISA and VIDAS® assays over rapid diagnostic IgM/IgG tests. The analytical performance of VIDAS® anti-CHIKV IgM and IgG assays was excellent, with a high precision (coefficients of variation ≤ 7.4%) and high specificity (cross-reactivity rate ≤ 2.9%). This study demonstrates the suitability of the automated VIDAS® anti-CHIKV IgM and IgG assays to diagnose CHIKV infections and supports its applicability for epidemiological surveillance and differential diagnosis in regions endemic for CHIKV.

7.
Viruses ; 15(6)2023 05 29.
Artículo en Inglés | MEDLINE | ID: mdl-37376568

RESUMEN

Introduction-The dynamics of SARS-CoV-2 shedding and replication in humans remain incompletely understood. Methods-We analyzed SARS-CoV-2 shedding from multiple sites in individuals with an acute COVID-19 infection by weekly sampling for five weeks in 98 immunocompetent and 25 immunosuppressed individuals. Samples and culture supernatants were tested via RT-PCR for SARS-CoV-2 to determine viral clearance rates and in vitro replication. Results-A total of 2447 clinical specimens were evaluated, including 557 nasopharyngeal swabs, 527 saliva samples, 464 urine specimens, 437 anal swabs and 462 blood samples. The SARS-CoV-2 genome sequences at each site were classified as belonging to the B.1.128 (ancestral strain) or Gamma lineage. SARS-CoV-2 detection was highest in nasopharyngeal swabs regardless of the virus strain involved or the immune status of infected individuals. The duration of viral shedding varied between clinical specimens and individual patients. Prolonged shedding of potentially infectious virus varied from 10 days up to 191 days, and primarily occurred in immunosuppressed individuals. Virus was isolated in culture from 18 nasal swab or saliva samples collected 10 or more days after onset of disease. Conclusions-Our findings indicate that persistent SARS-CoV-2 shedding may occur in both competent or immunosuppressed individuals, at multiple clinical sites and in a minority of subjects is capable of in vitro replication.


Asunto(s)
COVID-19 , Humanos , COVID-19/diagnóstico , SARS-CoV-2/genética , Prueba de COVID-19 , Manejo de Especímenes , Esparcimiento de Virus , ARN Viral/genética
8.
Anal Chim Acta ; 1257: 341167, 2023 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-37062564

RESUMEN

The world is in a long pandemic period caused by the SARS-CoV-2 virus and massive diagnostic tests to assist efforts to control the spread of the disease and also to avoid new coronavirus variants are still needed. Herein, we propose a simple and accurate saliva-based colorimetric test for the diagnosis of COVID-19. Magnetic beads (MBs) modified with a sequence of single-strand DNA (ssDNA) complementary to the N gene of the SARS-CoV-2 RNA were developed and used for magnetic capture and separation from a complex saliva sample. A second biotinylated ssDNA sequence was applied, and the colorimetric detection was carried out by adding streptavidin-horseradish peroxidase conjugate, H2O2, and tetramethylbenzidine (TMB) as chromogenic substrate. The test does not require viral RNA isolation, transcription, or amplification steps and can be performed at room temperature. The molecular assay test can be run using 96-well microplates, allowing the diagnosis of a large number of samples in 90 min. A simple support for magnets was designed and constructed using a 3D printer that allows the magnetic separations directly in the 96-well microplate. The colorimetric test showed an excellent ability to discriminate between healthy individuals and patients infected with SARS-CoV-2, with 92% and 100% of clinical sensitivity and specificity, respectively. This performance was similar to that achieved using the gold standard RT-PCR technique. The proposed genomagnetic assay offers an opportunity to greatly increase population testing, contribute to controlling the spread of the virus, and improve health equity in testing for COVID-19.


Asunto(s)
COVID-19 , Humanos , COVID-19/diagnóstico , SARS-CoV-2/genética , Prueba de COVID-19 , ARN Viral/genética , Colorimetría/métodos , Sensibilidad y Especificidad , Técnicas de Amplificación de Ácido Nucleico/métodos
9.
PLoS Negl Trop Dis ; 17(1): e0011037, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36608155

RESUMEN

BACKGROUND: Chikungunya-fever (CHIKF) remains a public health major issue. It is clinically divided into three phases: acute, post-acute and chronic. Chronic cases correspond to 25-40% individuals and, though most of them are characterized by long-lasting arthralgia alone, many of them exhibit persistent or recurrent inflammatory signs that define post-Chikungunya chronic inflammatory joint disease (pCHIKV-CIJD). We aimed to identify early clinical markers of evolution to pCHIKV-CIJD during acute and post-acute phases. METHODOLOGY/PRINCIPAL FINDINGS: We studied a prospective cohort of CHIKF-confirmed volunteers with longitudinal clinical data collection from symptoms onset up to 90 days, including a 21-day visit (D21). Of 169 patients with CHIKF, 86 (50.9%) completed the follow-up, from whom 39 met clinical criteria for pCHIKV-CIJD (45.3%). The relative risk of chronification was higher in women compared to men (RR = 1.52; 95% CI = 1.15-1.99; FDR = 0.03). None of the symptoms or signs presented at D0 behaved as an early predictor of pCHIKV-CIJD, while being symptomatic at D21 was a risk factor for chronification (RR = 1.31; 95% CI = 1.09-1.55; FDR = 0.03). Significance was also observed for joint pain (RR = 1.35; 95% CI = 1.12-1.61; FDR = 0.02), reported edema (RR = 3.61; 95% CI = 1.44-9.06; FDR = 0.03), reported hand and/or feet small joints edema (RR = 4.22; 95% CI = 1.51-11.78; FDR = 0.02), and peri-articular edema observed during physical examination (RR = 2.89; 95% CI = 1.58-5.28; FDR = 0.002). Furthermore, patients with no findings in physical examination at D21 were at lower risk of chronic evolution (RR = 0.41, 95% CI = 0.24-0.70, FDR = 0.01). Twenty-nine pCHIKV-CIJD patients had abnormal articular ultrasonography (90.6% of the examined). The most common findings were synovitis (65.5%) and joint effusion (58.6%). CONCLUSION: This cohort has provided important insights into the prognostic evaluation of CHIKF. Symptomatic sub-acute disease is a relevant predictor of evolution to chronic arthritis with synovitis, drawing attention to joint pain, edema, multiple articular involvement including small hand and feet joints as risk factors for chronification beyond three months, especially in women. Future studies are needed to accomplish the identification of accurate and early biomarkers of poor clinical prognosis, which would allow better understanding of the disease's evolution and improve patients' management, modifying CHIKF burden on global public health.


Asunto(s)
Artritis , Fiebre Chikungunya , Sinovitis , Masculino , Humanos , Femenino , Fiebre Chikungunya/complicaciones , Fiebre Chikungunya/diagnóstico , Fiebre Chikungunya/epidemiología , Estudios Prospectivos , Brasil/epidemiología , Artralgia/epidemiología , Artralgia/etiología , Biomarcadores , Enfermedad Crónica
10.
Artículo en Inglés | MEDLINE | ID: mdl-36197424

RESUMEN

COVID-19 disease is spread worldwide and diagnostic techniques have been studied in order to contain the pandemic. Immunochromatographic (IC) assays are feasible and a low-cost alternative especially in low and middle-income countries, which lack structure to perform certain diagnostic techniques. Here we evaluate the sensitivity and specificity of eleven different IC tests in 145 serum samples from confirmed cases of COVID-19 using RT-PCR and 100 negative serum samples from blood donors collected in February 2019. We also evaluated the cross-reactivity with dengue using 20 serum samples from patients with confirmed diagnosis for dengue collected in early 2019 through four different tests. We found high sensitivity (92%), specificity (100%) and an almost perfect agreement (Kappa 0.92) of IC assay, especially when we evaluated IgG and IgM combined after 10 days from the onset of symptoms with RT-PCR. However, we detected cross-reactivity between dengue and COVID-19 mainly with IgM antibodies (5 to 20% of cross-reaction) and demonstrated the need for better studies about diagnostic techniques for these diseases.


Asunto(s)
COVID-19 , Dengue , Anticuerpos Antivirales , COVID-19/diagnóstico , Dengue/diagnóstico , Humanos , Inmunoensayo/métodos , Inmunoglobulina G , Inmunoglobulina M , SARS-CoV-2 , Sensibilidad y Especificidad
11.
Artículo en Inglés | MEDLINE | ID: mdl-36074449

RESUMEN

In 2022, an outbreak of monkeypox is being reported in non-endemic areas, with unusual clinical manifestations. The detailed clinical description of the first patient that received the diagnosis of monkeypox in Brazil is reported here, whose clinical manifestations can easily lead to misdiagnosis of sexually transmitted infections. A 41 years old male presented to an emergency room with a vesicular rash with eight days of evolution. He had traveled to Portugal and Spain and reported non-penetrative sexual involvement with three different male individuals. On the third day of symptoms, he sought medical care and received empirical treatment directed to sexually transmitted infections. As the symptoms did not improve, he sought medical attention at an infectious disease referral center presenting, on admission, an ulcerated penile lesion with central necrotic crusts, a disseminated pleomorphic skin rash and an oropharyngeal ulcer. The monkeypox diagnosis was suspected due to the characteristics of the lesions and the history of intimate contact with casual partners, and it was later confirmed by sequencing the almost complete monkeypox genome. The patient was hospitalized for pain control, which required opiate administration. He developed a secondary bacterial infection on the penile lesions, which were treated with oral antibiotics. He was discharged after 14 days, with lesions in process of re-epithelialization. Given the current outbreak, we must consider the possibility of monkeypox in patients with suggestive lesions, anywhere on the body (including the genitals), added to an epidemiological link or history of intimate contact with strangers or casual partners.


Asunto(s)
Mpox , Enfermedades de Transmisión Sexual , Adulto , Animales , Brasil , Diagnóstico Diferencial , Brotes de Enfermedades , Humanos , Masculino , Mpox/diagnóstico , Mpox/epidemiología , Mpox/patología , Enfermedades de Transmisión Sexual/diagnóstico , Enfermedades de Transmisión Sexual/epidemiología
12.
Biologicals ; 80: 43-52, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36175304

RESUMEN

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), first identified in Wuhan, China, is the causative agent of the coronavirus disease 2019 (COVID-19). Since its first notification in São Paulo state (SP) on 26th February 2020, more than 22,300,000 cases and 619,000 deaths were reported in Brazil. In early pandemic, SARS-CoV-2 spread locally, however, over time, this virus was disseminated to other regions of the country. Herein, we performed genomic sequencing and phylogenetic analysis of SARS-CoV-2 using 20 clinical samples of COVID-19 confirmed cases from 9 cities of Minas Gerais state (MG), in order to evaluate the molecular properties of circulating viral strains in this locality from March to May 2020. Our analyses demonstrated the circulation of B.1 lineage isolates in the investigated locations and nucleotide substitutions were observed into the genomic regions related to important viral structures. Additionally, sequences generated in this study clustered with isolates from SP, suggesting a dissemination route between these two states. Alternatively, monophyletic groups of sequences from MG and other states or country were observed, indicating independent events of virus introduction. These results reinforce the need of genomic surveillance for understand the ongoing spread of emerging viral pathogens.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/epidemiología , Filogenia , Brasil/epidemiología , Genoma Viral/genética
14.
Clinics (Sao Paulo) ; 77: 100068, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35767900

RESUMEN

OBJECTIVES: The aim of the present study was to evaluate if neutralizing antibody responses induced by infection with the SARS-CoV-2 strain that was dominant at the beginning of the pandemic or by the Gamma variant was effective against the Omicron variant. METHODS: Convalescent sera from 109 individuals, never exposed to a SARS-CoV-2 vaccine, who had mild or moderate symptoms not requiring hospitalization following either a documented SARS-CoV-2 ancestral strain infection or a Gamma variant infection, were assayed for in vitro neutralizing antibody activity against their original strains and the Omicron variant. RESULTS: Following an infection with the ancestral strain, 56 (93.3%), 45 (77.6%) and 1 (1.7%) serum sample were positive for neutralizing antibodies against the ancestral, Gamma variant, and Omicron variant, respectively. After infection with the Gamma variant, 43 (87.8%) and 2 (4.1%) sera were positive for neutralizing antibodies against the Gamma and Omicron variants, respectively. CONCLUSIONS: Neutralizing antibodies generated following mild or moderate infection with the SARS-CoV-2 ancestral strain or the Gamma variant are not protective against the Omicron variant.


Asunto(s)
Anticuerpos Neutralizantes , COVID-19 , Anticuerpos Antivirales , COVID-19/terapia , Vacunas contra la COVID-19 , Humanos , Inmunización Pasiva , Pruebas de Neutralización , SARS-CoV-2 , Sueroterapia para COVID-19
15.
Travel Med Infect Dis ; 48: 102351, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35537676

RESUMEN

BACKGROUND: Only two naturally occurring human Sabiá virus (SABV) infections have been reported, and those occurred over 20 years ago. METHODS: We diagnosed two new cases of SABV infection using metagenomics in patients thought to have severe yellow fever and described new features of histopathological findings. RESULTS: We characterized clinical manifestations, histopathology and analyzed possible nosocomial transmission. Patients presented with hepatitis, bleeding, neurological alterations and died. We traced twenty-nine hospital contacts and evaluated them clinically and by RT-PCR and neutralizing antibodies. Autopsies uncovered unique features on electron microscopy, such as hepatocyte "pinewood knot" lesions. Although previous reports with similar New-World arenavirus had nosocomial transmission, our data did not find any case in contact tracing. CONCLUSIONS: Although an apparent by rare, Brazilian mammarenavirus infection is an etiology for acute hemorrhagic fever syndrome. The two fatal cases had peculiar histopathological findings not previously described. The virological diagnosis was possible only by contemporary techniques such as metagenomic assays. We found no subsequent infections when we used serological and molecular tests to evaluate close contacts.


Asunto(s)
Arenavirus del Nuevo Mundo , Infección Hospitalaria , Fiebre Amarilla , Anticuerpos Neutralizantes , Brasil/epidemiología , Humanos
16.
Biosens Bioelectron ; 199: 113866, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34915214

RESUMEN

The outbreak of COVID-19 pandemics highlighted the need of sensitive, selective, and easy-to-handle biosensing devices. In the contemporary scenario, point-of-care devices for mass testing and infection mapping within a population have proven themselves as of primordial importance. Here, we introduce a graphene-based Electrical-Electrochemical Vertical Device (EEVD) point-of-care biosensor, strategically engineered for serologic COVID-19 diagnosis. EEVD uses serologic IgG quantifications on SARS-CoV-2 Receptor Binding Domain (RBD) bioconjugate immobilized onto device surface. EEVD combines graphene basal plane with high charge carrier mobility, high conductivity, low intrinsic resistance, and interfacial sensitivity to capacitance alterations. EEVD application was carried out in real human serum samples. Since EEVD is a miniaturized device, it requires just 40 µL of sample for a point-of-care COVID-19 infections detection. When compared to serologic assays such ELISA and other immunochromatographic methods, EEVD presents some advantages such as time of analyses (15 min), sample preparation, and a LOD of 1.0 pg mL-1. We glimpse that EEVD meets the principles of robustness and accuracy, desirable analytic parameters for assays destined to pandemics control strategies.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Grafito , Anticuerpos Antivirales , Prueba de COVID-19 , Humanos , Sistemas de Atención de Punto , SARS-CoV-2 , Sensibilidad y Especificidad , Pruebas Serológicas
17.
Clinics ; Clinics;77: 100068, 2022. tab
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1394284

RESUMEN

Abstract Objectives: The aim of the present study was to evaluate if neutralizing antibody responses induced by infection with the SARS-CoV-2 strain that was dominant at the beginning of the pandemic or by the Gamma variant was effective against the Omicron variant. Methods: Convalescent sera from 109 individuals, never exposed to a SARS-CoV-2 vaccine, who had mild or moderate symptoms not requiring hospitalization following either a documented SARS-CoV-2 ancestral strain infection or a Gamma variant infection, were assayed for in vitro neutralizing antibody activity against their original strains and the Omicron variant. Results: Following an infection with the ancestral strain, 56 (93.3%), 45 (77.6%) and 1 (1.7%) serum sample were positive for neutralizing antibodies against the ancestral, Gamma variant, and Omicron variant, respectively. After infection with the Gamma variant, 43 (87.8%) and 2 (4.1%) sera were positive for neutralizing antibodies against the Gamma and Omicron variants, respectively. Conclusions: Neutralizing antibodies generated following mild or moderate infection with the SARS-CoV-2 ancestral strain or the Gamma variant are not protective against the Omicron variant. HIGHLIGHTS Individuals previously infected with SARS-CoV-2 ancestral strain do not develop neutralizing antibodies against the Omicron variant. Omicron variant escapes immune response after SARS CoV-2 previous infection with the SARS CoV-2 Gamma variant. Individuals previously infected with SARS-CoV-2 ancestral strain or with SARS-CoV-2 Gamma variant will likely have little protection if subsequently exposed to the Omicron variant.

18.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1406880

RESUMEN

ABSTRACT In 2022, an outbreak of monkeypox is being reported in non-endemic areas, with unusual clinical manifestations. The detailed clinical description of the first patient that received the diagnosis of monkeypox in Brazil is reported here, whose clinical manifestations can easily lead to misdiagnosis of sexually transmitted infections. A 41 years old male presented to an emergency room with a vesicular rash with eight days of evolution. He had traveled to Portugal and Spain and reported non-penetrative sexual involvement with three different male individuals. On the third day of symptoms, he sought medical care and received empirical treatment directed to sexually transmitted infections. As the symptoms did not improve, he sought medical attention at an infectious disease referral center presenting, on admission, an ulcerated penile lesion with central necrotic crusts, a disseminated pleomorphic skin rash and an oropharyngeal ulcer. The monkeypox diagnosis was suspected due to the characteristics of the lesions and the history of intimate contact with casual partners, and it was later confirmed by sequencing the almost complete monkeypox genome. The patient was hospitalized for pain control, which required opiate administration. He developed a secondary bacterial infection on the penile lesions, which were treated with oral antibiotics. He was discharged after 14 days, with lesions in process of re-epithelialization. Given the current outbreak, we must consider the possibility of monkeypox in patients with suggestive lesions, anywhere on the body (including the genitals), added to an epidemiological link or history of intimate contact with strangers or casual partners.

19.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1406886

RESUMEN

ABSTRACT COVID-19 disease is spread worldwide and diagnostic techniques have been studied in order to contain the pandemic. Immunochromatographic (IC) assays are feasible and a low-cost alternative especially in low and middle-income countries, which lack structure to perform certain diagnostic techniques. Here we evaluate the sensitivity and specificity of eleven different IC tests in 145 serum samples from confirmed cases of COVID-19 using RT-PCR and 100 negative serum samples from blood donors collected in February 2019. We also evaluated the cross-reactivity with dengue using 20 serum samples from patients with confirmed diagnosis for dengue collected in early 2019 through four different tests. We found high sensitivity (92%), specificity (100%) and an almost perfect agreement (Kappa 0.92) of IC assay, especially when we evaluated IgG and IgM combined after 10 days from the onset of symptoms with RT-PCR. However, we detected cross-reactivity between dengue and COVID-19 mainly with IgM antibodies (5 to 20% of cross-reaction) and demonstrated the need for better studies about diagnostic techniques for these diseases.

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