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2.
Bratisl Lek Listy ; 122(1): 11-17, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33393315

RESUMEN

AbstractAIMS: Aims: The Coronavirus Disease 2019 (COVID-19) caused not only global pandemic, but it also pointed at unprepared health care systems and countermeasures were introduced under the pressure of urgent circumstances. This review is focused on discussion and critical evaluation of instrumental tools for COVID-19 diagnosis that were developed in the last months. METHODS: Survey of actual literature and scientific reports was made. The most substantial analytical and diagnostical methods were identified and described. Principles and limitations of the methods are described, and actual papers are cited in this review. RESULTS: Analytical and diagnostical methods like Polymerase Chain Reaction (PCR), Loop-mediated isothermal Amplification (LAMP), Lateral Flow Immunochromatography Assay (LFIA), Enzyme-Linked Immunosorbent Assay (ELISA), biosensors and ChemiLuminescence ImmunoAssay (CLIA) are discussed for assay of viral particles, antigens and specific host antibodies in blood, serum, plasma, nasopharyngeal swab and other samples in order to diagnose COVID-19. CONCLUSIONS: The Coronavirus Disease 2019 (COVID-19) is an emerging disease that has spread over the world since the end of year 2019. The global epidemic pointed at the necessity to introduce sensitive methods for instrumental diagnosis of COVID-19 and distinguishing it from the other viral diseases. (Tab. 2, Ref. 96).


Asunto(s)
Anticuerpos Antivirales , Técnicas de Laboratorio Clínico , Humanos , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico
3.
Talanta ; 222: 121534, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33167242

RESUMEN

As COVID-19 has reached pandemic status and the number of cases continues to grow, widespread availability of diagnostic testing is critical in helping identify and control the emergence of this rapidly spreading and serious illness. However, a lacking in making a quick reaction to the threat and starting early development of diagnostic sensing tools has had an important impact globally. In this regard, here we will review critically the current developed diagnostic tools in response to the COVID-19 pandemic and compare the different types through the discussion of their pros and cons such as nucleic acid detection tests (including PCR and CRISPR), antibody and protein-based diagnosis tests. In addition, potential technologies that are under development such as on-site diagnosis platforms, lateral flow, and portable PCR units are discussed. Data collection and epidemiological analysis could also be an interesting factor to incorporate with the emerging technologies especially with the wide access to smartphones. Lastly, a SWOT analysis and perspectives on how the development of novel sensory platforms should be treated by the different decision-makers are analyzed.


Asunto(s)
Técnicas de Laboratorio Clínico/métodos , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/epidemiología , Pandemias , Neumonía Viral/diagnóstico , Neumonía Viral/epidemiología , Técnicas de Laboratorio Clínico/instrumentación , Humanos , Pruebas en el Punto de Atención , Juego de Reactivos para Diagnóstico
4.
Front Biosci (Elite Ed) ; 13: 117-139, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33048778

RESUMEN

Coronavirus disease (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a member of the human coronavirus (HCoV) family that targets the lower part of the respiratory tract and causes severe acute respiratory syndrome (SARS). In a short span of time, this infection has led to a global pandemic and has become a significant threat to the existence of present human society. Currently, there are no treatments for this infection and the measures established across various countries such as social distancing, usage of mask to prevent entry of the virus into the respiratory tract, quarantine, and containment together have reduced the prevalence of this disease and mortality in highly susceptible individuals. Here, we examine the structure, replication cycle, phylogeny and genomic organization of this virus and discuss the role of spike (S) protein of the virus, an important structure that interacts with the host ACE2 receptor facilitating viral entry. Further, we explore the epidemiology, symptoms of the disease, describe the reverse transcriptase-polymerase chain reaction (RT-PCR) that establishes the diagnosis of the disease and also review its unique diagnostic features in the chest CT-Scan. Finally, we review the current approaches to develop therapies and vaccines as a measure for disease prevention and control.


Asunto(s)
Betacoronavirus/aislamiento & purificación , Infecciones por Coronavirus/epidemiología , Pandemias , Neumonía Viral/epidemiología , Técnicas de Laboratorio Clínico/métodos , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/terapia , Infecciones por Coronavirus/virología , Humanos , Neumonía Viral/diagnóstico , Neumonía Viral/terapia , Neumonía Viral/virología
5.
Ann Med ; 53(1): 151-159, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33138653

RESUMEN

OBJECTIVE: To utilize publicly reported, state-level data to identify factors associated with the frequency of cases, tests, and mortality in the USA. MATERIALS AND METHODS: Retrospective study using publicly reported data collected included the number of COVID-19 cases, tests and mortality from March 14th through April 30th. Publicly available state-level data was collected which included: demographics comorbidities, state characteristics and environmental factors. Univariate and multivariate regression analyses were performed to identify the significantly associated factors with percent mortality, case and testing frequency. All analyses were state-level analyses and not patient-level analyses. RESULTS: A total of 1,090,500 COVID-19 cases were reported during the study period. The calculated case and testing frequency were 3332 and 19,193 per 1,000,000 patients. There were 63,642 deaths during this period which resulted in a mortality of 5.8%. Factors including to but not limited to population density (beta coefficient 7.5, p < .01), transportation volume (beta coefficient 0.1, p < .01), tourism index (beta coefficient -0.1, p = .02) and older age (beta coefficient 0.2, p = .01) are associated with case frequency and percent mortality. CONCLUSIONS: There were wide variations in testing and case frequencies of COVID-19 among different states in the US. States with higher population density had a higher case and testing rate. States with larger population of elderly and higher tourism had a higher mortality. Key messages There were wide variations in testing and case frequencies of COVID-19 among different states in the USA. States with higher population density had a higher case and testing rate. States with larger population of elderly and higher tourism had a higher mortality.


Asunto(s)
Técnicas de Laboratorio Clínico/estadística & datos numéricos , Infecciones por Coronavirus/mortalidad , Neumonía Viral/mortalidad , Comorbilidad , Infecciones por Coronavirus/diagnóstico , Femenino , Disparidades en Atención de Salud , Humanos , Masculino , Pandemias , Neumonía Viral/diagnóstico , Estados Unidos/epidemiología
6.
Biosens Bioelectron ; 171: 112686, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33086175

RESUMEN

The diffusion of novel SARS-CoV-2 coronavirus over the world generated COVID-19 pandemic event as reported by World Health Organization on March 2020. The huge issue is the high infectivity and the absence of vaccine and customised drugs allowing for hard management of this outbreak, thus a rapid and on site analysis is a need to contain the spread of COVID-19. Herein, we developed an electrochemical immunoassay for rapid and smart detection of SARS-CoV-2 coronavirus in saliva. The electrochemical assay was conceived for Spike (S) protein or Nucleocapsid (N) protein detection using magnetic beads as support of immunological chain and secondary antibody with alkaline phosphatase as immunological label. The enzymatic by-product 1-naphtol was detected using screen-printed electrodes modified with carbon black nanomaterial. The analytical features of the electrochemical immunoassay were evaluated using the standard solution of S and N protein in buffer solution and untreated saliva with a detection limit equal to 19 ng/mL and 8 ng/mL in untreated saliva, respectively for S and N protein. Its effectiveness was assessed using cultured virus in biosafety level 3 and in saliva clinical samples comparing the data using the nasopharyngeal swab specimens tested with Real-Time PCR. The agreement of the data, the low detection limit achieved, the rapid analysis (30 min), the miniaturization, and portability of the instrument combined with the easiness to use and no-invasive sampling, confer to this analytical tool high potentiality for market entry as the first highly sensitive electrochemical immunoassay for SARS-CoV-2 detection in untreated saliva.


Asunto(s)
Betacoronavirus/aislamiento & purificación , Técnicas Biosensibles/instrumentación , Técnicas de Laboratorio Clínico , Infecciones por Coronavirus/diagnóstico , Neumonía Viral/diagnóstico , Saliva/virología , Técnicas Electroquímicas/instrumentación , Electrodos , Diseño de Equipo , Humanos , Inmunoensayo/instrumentación , Imanes/química , Proteínas de la Nucleocápside/análisis , Pandemias , Fosfoproteínas , Sensibilidad y Especificidad , Hollín/química , Glicoproteína de la Espiga del Coronavirus/análisis
7.
MMWR Morb Mortal Wkly Rep ; 69(5152): 1648-1652, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33382673

RESUMEN

On January 30, 2020, the World Health Organization (WHO) declared coronavirus disease 2019 (COVID-19) a Public Health Emergency of International Concern (1). On March 24, 2020, the Global Polio Eradication Initiative (GPEI) suspended all polio supplementary immunization activities and recommended the continuation of polio surveillance (2). In April 2020, GPEI shared revised polio surveillance guidelines in the context of the COVID-19 pandemic, which focused on reducing the risk for transmission of SARS-CoV-2, the virus that causes COVID-19, to health care workers and communities by modifying activities that required person-to-person contact, improving hand hygiene and personal protective equipment use practices, and overcoming challenges related to movement restrictions, while continuing essential polio surveillance functions (3). GPEI assessed the impact of the COVID-19 pandemic on polio surveillance by comparing data from January to September 2019 to the same period in 2020. Globally, the number of acute flaccid paralysis (AFP) cases reported declined 33% and the mean number of days between the second stool collected and receipt by the laboratory increased by 70%. Continued analysis of AFP case reporting and stool collection is critical to ensure timely detection and response to interruptions of polio surveillance.


Asunto(s)
Salud Global , Poliomielitis/epidemiología , Vigilancia de la Población , Técnicas de Laboratorio Clínico/estadística & datos numéricos , Erradicación de la Enfermedad , Heces/virología , Humanos , Poliomielitis/prevención & control , Poliovirus/aislamiento & purificación , Vacunas contra Poliovirus/administración & dosificación
8.
CMAJ ; 193(1): E1-E9, 2021 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-33234533

RESUMEN

BACKGROUND: Research involving children with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has primarily focused on those presenting to emergency departments. We aimed to determine the symptoms most commonly associated with a positive result for a SARS-CoV-2 swab among community-based children. METHODS: We conducted an observational study among children tested and followed for SARS-CoV-2 infection using nasal, nasopharyngeal, throat or other (e.g., nasopharyngeal aspirate or tracheal secretions, or unknown) swabs between Apr. 13 and Sept. 30, 2020, in Alberta. We calculated positive likelihood ratios (LRs) for self-reported symptoms and a positive SARS-CoV-2 swab result in the entire cohort and in 3 sensitivity analyses: all children with at least 1 symptom, all children tested because of contact tracing whether they were symptomatic or not and all children 5 years of age or older. RESULTS: We analyzed results for 2463 children who underwent testing for SARS-CoV-2 infection; 1987 children had a positive result and 476 had a negative result. Of children with a positive test result for SARS-CoV-2, 714 (35.9%) reported being asymptomatic. Although cough (24.5%) and rhinorrhea (19.3%) were 2 of the most common symptoms among children with SARS-CoV-2 infection, they were also common among those with negative test results and were not predictive of a positive test (positive LR 0.96, 95% confidence interval [CI] 0.81-1.14, and 0.87, 95% CI 0.72-1.06, respectively). Anosmia/ageusia (positive LR 7.33, 95% CI 3.03-17.76), nausea/vomiting (positive LR 5.51, 95% CI 1.74-17.43), headache (positive LR 2.49, 95% CI 1.74- 3.57) and fever (positive LR 1.68, 95% CI 1.34-2.11) were the symptoms most predictive of a positive result for a SARS-CoV-2 swab. The positive LR for the combination of anosmia/ageusia, nausea/vomiting and headache was 65.92 (95% CI 49.48-91.92). INTERPRETATION: About two-thirds of the children who tested positive for SARS-CoV-2 infection reported symptoms. The symptoms most strongly associated with a positive SARS-CoV-2 swab result were anosmia/ageusia, nausea/vomiting, headache and fever.


Asunto(s)
/diagnóstico , Técnicas de Laboratorio Clínico/métodos , Pandemias , Manejo de Especímenes/métodos , Adolescente , Alberta/epidemiología , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino
9.
Biosens Bioelectron ; 171: 112715, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33099241

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19), a newly emerging human infectious disease. Because no specific antiviral drugs or vaccines are available to treat COVID-19, early diagnostics, isolation, and prevention are crucial for containing the outbreak. Molecular diagnostics using reverse transcription polymerase chain reaction (RT-PCR) are the current gold standard for detection. However, viral RNAs are much less stable during transport and storage than proteins such as antigens and antibodies. Consequently, false-negative RT-PCR results can occur due to inadequate collection of clinical specimens or poor handling of a specimen during testing. Although antigen immunoassays are stable diagnostics for detection of past infection, infection progress, and transmission dynamics, no matched antibody pair for immunoassay of SARS-CoV-2 antigens has yet been reported. In this study, we designed and developed a novel rapid detection method for SARS-CoV-2 spike 1 (S1) protein using the SARS-CoV-2 receptor ACE2, which can form matched pairs with commercially available antibodies. ACE2 and S1-mAb were paired with each other for capture and detection in a lateral flow immunoassay (LFIA) that did not cross-react with SARS-CoV Spike 1 or MERS-CoV Spike 1 protein. The SARS-CoV-2 S1 (<5 ng of recombinant proteins/reaction) was detected by the ACE2-based LFIA. The limit of detection of our ACE2-LFIA was 1.86 × 105 copies/mL in the clinical specimen of COVID-19 Patients without no cross-reactivity for nasal swabs from healthy subjects. This is the first study to detect SARS-CoV-2 S1 antigen using an LFIA with matched pair consisting of ACE2 and antibody. Our findings will be helpful to detect the S1 antigen of SARS-CoV-2 from COVID-19 patients.


Asunto(s)
Betacoronavirus/aislamiento & purificación , Técnicas Biosensibles/instrumentación , Técnicas de Laboratorio Clínico , Infecciones por Coronavirus/diagnóstico , Peptidil-Dipeptidasa A/química , Neumonía Viral/diagnóstico , Glicoproteína de la Espiga del Coronavirus/análisis , Anticuerpos Monoclonales/química , Técnicas Biosensibles/economía , Técnicas de Laboratorio Clínico/economía , Técnicas de Laboratorio Clínico/instrumentación , Infecciones por Coronavirus/economía , Diseño de Equipo , Humanos , Inmunoensayo/economía , Inmunoensayo/instrumentación , Inmunoconjugados/química , Pandemias , Sensibilidad y Especificidad , Factores de Tiempo
10.
Emerg Infect Dis ; 27(1)2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33183494

RESUMEN

Pooled nucleic acid amplification tests for severe acute respiratory syndrome coronavirus 2 could increase availability of testing at decreased cost. However, the effect of dilution on analytical sensitivity through sample pooling has not been well characterized. We tested 1,648 prospectively pooled specimens by using 3 nucleic acid amplification tests for severe acute respiratory syndrome coronavirus 2: a laboratory-developed real-time reverse transcription PCR targeting the envelope gene, and 2 commercially available Panther System assays targeting open reading frame 1ab. Positive percent agreement (PPA) of pooled versus individual testing ranged from 71.7% to 82.6% for pools of 8 and from 82.9% to 100.0% for pools of 4. We developed and validated an independent stochastic simulation model to estimate effects of dilution on PPA and efficiency of a 2-stage pooled real-time reverse transcription PCR testing algorithm. PPA was dependent on the proportion of tests with positive results, cycle threshold distribution, and assay limit of detection.


Asunto(s)
/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , /aislamiento & purificación , /virología , Técnicas de Laboratorio Clínico/métodos , Reacciones Falso Negativas , Humanos , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/normas , Estudios Prospectivos , Sensibilidad y Especificidad , Manejo de Especímenes , Procesos Estocásticos
11.
Biosens Bioelectron ; 171: 112685, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33113383

RESUMEN

The spread of SARS-CoV-2 virus in the ongoing global pandemic has led to infections of millions of people and losses of many lives. The rapid, accurate and convenient SARS-CoV-2 virus detection is crucial for controlling and stopping the pandemic. Diagnosis of patients in the early stage infection are so far limited to viral nucleic acid or antigen detection in human nasopharyngeal swab or saliva samples. Here we developed a method for rapid and direct optical measurement of SARS-CoV-2 virus particles in one step nearly without any sample preparation using a spike protein specific nanoplasmonic resonance sensor. As low as 370 vp/mL were detected in one step within 15 min and the virus concentration can be quantified linearly in the range of 0 to 107 vp/mL. Measurements shown on both generic microplate reader and a handheld smartphone connected device suggest that our low-cost and rapid detection method may be adopted quickly under both regular clinical environment and resource-limited settings.


Asunto(s)
Betacoronavirus/aislamiento & purificación , Técnicas Biosensibles/instrumentación , Técnicas de Laboratorio Clínico , Infecciones por Coronavirus/diagnóstico , Neumonía Viral/diagnóstico , Pruebas en el Punto de Atención , Virión/aislamiento & purificación , Anticuerpos Inmovilizados/química , Técnicas Biosensibles/economía , Técnicas de Laboratorio Clínico/economía , Infecciones por Coronavirus/economía , Diseño de Equipo , Humanos , Límite de Detección , Modelos Moleculares , Pandemias , Glicoproteína de la Espiga del Coronavirus/análisis , Factores de Tiempo
12.
Biosens Bioelectron ; 171: 112753, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33120235

RESUMEN

A polyethyleneimine (PEI)-assisted copper in-situ growth (CISG) strategy was proposed as a controlled signal amplification strategy to enhance the sensitivity of gold nanoparticle-based lateral flow sensors (AuNP-LFS). The controlled signal amplification is achieved by introducing PEI as a structure-directing agent to regulate the thermodynamics of anisotropic Cu nanoshell growth on the AuNP surface, thus controlling shape and size of the resultant AuNP@Cu core-shell nanostructures and confining free reduction and self-nucleation of Cu2+ for improved reproducibility and decreased false positives. The PEI-CISG-enhanced AuNP-LFS showed ultrahigh sensitivities with the detection limits of 50 fg mL-1 for HIV-1 capsid p24 antigen and 6 CFU mL-1 for Escherichia coli O157:H7. We further demonstrated its clinical diagnostic efficacy by configuring PEI-CISG into a commercial AuNP-LFS detection kit for SARS-CoV-2 antibody detection. Altogether, this work provides a reliable signal amplification platform to dramatically enhance the sensitivity of AuNP-LFS for rapid and accurate diagnostics of various infectious diseases.


Asunto(s)
Técnicas Biosensibles/métodos , Cobre/química , Infecciones por Coronavirus/diagnóstico , Infecciones por Escherichia coli/diagnóstico , Oro/química , Infecciones por VIH/diagnóstico , Neumonía Viral/diagnóstico , Betacoronavirus/aislamiento & purificación , Técnicas Biosensibles/instrumentación , Técnicas de Laboratorio Clínico , Diseño de Equipo , Escherichia coli O157/aislamiento & purificación , Proteína p24 del Núcleo del VIH/análisis , VIH-1/aislamiento & purificación , Humanos , Límite de Detección , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Oxidación-Reducción , Pandemias , Polietileneimina/química , Tiras Reactivas/análisis
13.
Am J Emerg Med ; 39: 143-145, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33039212

RESUMEN

Facing the novel coronavirus disease (COVID-19) pandemic, evidence to inform decision-making at all care levels is essential. Based on the results of a study by Petrilli et al., we have developed a calculator using patient data at admission to predict critical illness (intensive care, mechanical ventilation, hospice care, or death). We report a retrospective validation of the calculator on 145 consecutive patients admitted with COVID-19 to a single hospital in Israel. Despite considerable differences between the original and validation study populations, of 18 patients with critical illness, 17 were correctly identified (sensitivity: 94.4%, 95% CI, 72.7%-99.9%; specificity: 81.9%, 95% CI, 74.1%-88.2%). Of 127 patients with non-critical illness, 104 were correctly identified. Our results indicate that published knowledge can be reliably applied to assess patient risk, potentially reducing the cognitive burden on physicians, and helping policymakers better prepare for future needs.


Asunto(s)
/fisiopatología , Técnicas de Laboratorio Clínico/normas , Cuidados Críticos/organización & administración , Enfermedad Crítica/terapia , Anciano , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Israel , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Medición de Riesgo/normas , Factores de Riesgo
14.
Biosens Bioelectron ; 171: 112703, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33049563

RESUMEN

COVID-19 pandemic has affected everyone throughout the world and has resulted in the loss of lives of many souls. Due to the restless efforts of the researchers working hard day and night, some success has been gained for the detection of virus. As on date, the traditional polymerized chain reactions (PCR), lateral flow devices (LFID) and enzyme linked immunosorbent assays (ELISA) are being adapted for the detection of this deadly virus. However, a more exciting avenue is the detection of certain biomarkers associated with this viral infection which can be done by simply re-purposing our existing infrastructure. SARS-CoV-2 viral infection triggers various inflammatory, biochemical and hematological biomarkers. Because of the infection route that the virus follows, it causes significant inflammatory response. As a result, various inflammatory markers have been reported to be closely associated with this infection such as C-reactive proteins, interleukin-6, procalcitonin and ferritin. Sensing of these biomarkers can simultaneously help in understanding the illness level of the affected patient. Also, by monitoring these biomarkers, we can predict the viral infections in those patients who have low SARS-CoV-2 RNA and hence are missed by traditional tests. This can give more targets to the researchers and scientists, working in the area of drug development and provide better prognosis. In this review, we propose to highlight the conventional as well as the non-conventional methods for the detection of these inflammatory biomarkers which can act as a single platform of knowledge for the researchers and scientists working for the treatment of COVID-19.


Asunto(s)
Técnicas Biosensibles/métodos , Técnicas de Laboratorio Clínico , Infecciones por Coronavirus/diagnóstico , Inflamación/diagnóstico , Neumonía Viral/diagnóstico , Animales , Betacoronavirus/aislamiento & purificación , Biomarcadores/análisis , Técnicas Biosensibles/instrumentación , Proteína C-Reactiva/análisis , Diseño de Equipo , Ferritinas/análisis , Humanos , Interleucina-6/análisis , Pandemias , Polipéptido alfa Relacionado con Calcitonina/análisis
15.
J Infect Chemother ; 27(1): 126-129, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33060046

RESUMEN

Considering the issues of shortage of medical resources and the invasiveness and infection risk involved in the collection of nasopharyngeal swab specimens, there is a need for an effective alternative test specimen for SARS-CoV-2 RNA detection. Here, we investigated suitability of saliva as a non-invasively obtained specimen for molecular detection of SARS-CoV-2 RNA in Japanese patients with COVID-19. In total, 28 paired clinical specimens of saliva and nasopharyngeal swabs were collected from 12 patients at various time points after symptom onset. Each specimen was assayed using reverse transcription real-time polymerase chain reaction (rRT-PCR) on the BD MAX open system using primers and probes targeting the N-gene. The saliva and nasopharyngeal swab specimens showed 19 and 15 positive results, respectively. No invalid (PCR inhibition) result was observed for any specimen. The qualitative results of each specimen obtained in the period immediately after symptom onset were similar. Three convalescent patients presented saliva-positive results, whereas their nasopharyngeal swabs were negative at four different time points, suggesting that saliva may be superior to nasopharyngeal swabs in terms of obtaining stable assay result of SARS-CoV-2. In conclusion, our results suggest that saliva can potentially serve as an alternative to nasopharyngeal swabs as a specimen for SARS-CoV-2 rRT-PCR. As saliva can be collected by patients themselves, it may be an effective way to overcome the shortage of personal protective equipment and specimen sampling tools.


Asunto(s)
Betacoronavirus/aislamiento & purificación , Infecciones por Coronavirus/diagnóstico , Nasofaringe/virología , Neumonía Viral/diagnóstico , ARN Viral/aislamiento & purificación , Saliva/virología , Técnicas de Laboratorio Clínico , Humanos , Japón , Pandemias , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Manejo de Especímenes/métodos
16.
Biosens Bioelectron ; 171: 112716, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33068880

RESUMEN

With the aim of contributing to the fight against the coronavirus disease 2019 (COVID-19), numerous strategies have been proposed. While developing an effective vaccine can take months up to years, detection of infected patients seems like one of the best ideas for controlling the situation. The role of biosensors in containing highly pathogenic viruses, saving lives and economy is evident. A new competitive numerical platform specifically for designing microfluidic-integrated biosensors is developed and presented in this work. Properties of the biosensor, sample, buffer fluid and even the microfluidic channel can be modified in this model. This feature provides the scientific community with the ability to design a specific biosensor for requested point-of-care (POC) applications. First, the validation of the presented numerical platform against experimental data and then results and discussion, highlighting the important role of the design parameters on the performance of the biosensor is presented. For the latter, the baseline case has been set on the previous studies on the biosensors suitable for SARS-CoV, which has the highest similarity to the 2019 nCoV. Subsequently, the effects of concentration of the targeted molecules in the sample, installation position and properties of the biosensor on its performance were investigated in 11 case studies. The presented numerical framework provides an insight into understanding of the virus reaction in the design process of the biosensor and enhances our preparation for any future outbreaks. Furthermore, the integration of biosensors with different devices for accelerating the process of defeating the pandemic is proposed.


Asunto(s)
Betacoronavirus/aislamiento & purificación , Infecciones por Coronavirus/diagnóstico , Neumonía Viral/diagnóstico , Algoritmos , Técnicas Biosensibles , Técnicas de Laboratorio Clínico , Simulación por Computador , Sistemas de Computación , Humanos , Hidrodinámica , Técnicas Analíticas Microfluídicas , Pandemias , Sistemas de Atención de Punto
17.
Biosens Bioelectron ; 171: 112679, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33069957

RESUMEN

The 2019 SARS CoV-2 (COVID-19) pandemic has illustrated the need for rapid and accurate diagnostic tests. In this work, a multiplexed grating-coupled fluorescent plasmonics (GC-FP) biosensor platform was used to rapidly and accurately measure antibodies against COVID-19 in human blood serum and dried blood spot samples. The GC-FP platform measures antibody-antigen binding interactions for multiple targets in a single sample, and has 100% selectivity and sensitivity (n = 23) when measuring serum IgG levels against three COVID-19 antigens (spike S1, spike S1S2, and the nucleocapsid protein). The GC-FP platform yielded a quantitative, linear response for serum samples diluted to as low as 1:1600 dilution. Test results were highly correlated with two commercial COVID-19 antibody tests, including an enzyme linked immunosorbent assay (ELISA) and a Luminex-based microsphere immunoassay. To demonstrate test efficacy with other sample matrices, dried blood spot samples (n = 63) were obtained and evaluated with GC-FP, yielding 100% selectivity and 86.7% sensitivity for diagnosing prior COVID-19 infection. The test was also evaluated for detection of multiple immunoglobulin isotypes, with successful detection of IgM, IgG and IgA antibody-antigen interactions. Last, a machine learning approach was developed to accurately score patient samples for prior COVID-19 infection, using antibody binding data for all three COVID-19 antigens used in the test.


Asunto(s)
Anticuerpos Antivirales/sangre , Betacoronavirus/inmunología , Técnicas Biosensibles/instrumentación , Técnicas de Laboratorio Clínico , Infecciones por Coronavirus/sangre , Neumonía Viral/sangre , Anticuerpos Antivirales/inmunología , Betacoronavirus/aislamiento & purificación , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/inmunología , Pruebas con Sangre Seca , Diseño de Equipo , Fluorescencia , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Dispositivos Laboratorio en un Chip , Pandemias , Neumonía Viral/diagnóstico , Neumonía Viral/inmunología , Sensibilidad y Especificidad
18.
Biosens Bioelectron ; 171: 112709, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33075724

RESUMEN

Coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was classified as a pandemic by the World Health Organization and has caused over 550,000 deaths worldwide as of July 2020. Accurate and scalable point-of-care devices would increase screening, diagnosis, and monitoring of COVID-19 patients. Here, we demonstrate rapid label-free electrochemical detection of SARS-CoV-2 antibodies using a commercially available impedance sensing platform. A 16-well plate containing sensing electrodes was pre-coated with receptor binding domain (RBD) of SARS-CoV-2 spike protein, and subsequently tested with samples of anti-SARS-CoV-2 monoclonal antibody CR3022 (0.1 µg/ml, 1.0 µg/ml, 10 µg/ml). Subsequent blinded testing was performed on six serum specimens taken from COVID-19 and non-COVID-19 patients (1:100 dilution factor). The platform was able to differentiate spikes in impedance measurements from a negative control (1% milk solution) for all CR3022 samples. Further, successful differentiation and detection of all positive clinical samples from negative control was achieved. Measured impedance values were consistent when compared to standard ELISA test results showing a strong correlation between them (R2=0.9). Detection occurs in less than five minutes and the well-based platform provides a simplified and familiar testing interface that can be readily adaptable for use in clinical settings.


Asunto(s)
Anticuerpos Antivirales/sangre , Betacoronavirus/inmunología , Técnicas Biosensibles/instrumentación , Técnicas de Laboratorio Clínico , Infecciones por Coronavirus/sangre , Espectroscopía Dieléctrica/instrumentación , Neumonía Viral/sangre , Anticuerpos Antivirales/inmunología , Técnicas Biosensibles/economía , Técnicas de Laboratorio Clínico/economía , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/economía , Infecciones por Coronavirus/inmunología , Espectroscopía Dieléctrica/economía , Impedancia Eléctrica , Diseño de Equipo , Humanos , Proteínas Inmovilizadas/inmunología , Pandemias , Neumonía Viral/diagnóstico , Neumonía Viral/inmunología , Sensibilidad y Especificidad , Glicoproteína de la Espiga del Coronavirus/inmunología , Factores de Tiempo
19.
Biosens Bioelectron ; 171: 112731, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33075725

RESUMEN

Rapid person-to-person transfer of viruses such as SARS-CoV-2 and their occasional mutations owing to the human activity and climate/ecological changes by the mankind led to creation of wrecking worldwide challenges. Such fast transferable pathogens requiring practical diagnostic setups to control their transfer chain and stop sever outbreaks in early stages of their appearance. Herein, we have addressed this urgent demand by designing a rapid electrochemical diagnostic kit composed of fixed/screen printed electrodes that can detect pathogenic viruses such as SARS-CoV-2 and/or animal viruses through the differentiable fingerprint of their viral glycoproteins at different voltage positions. The working electrode of developed sensor is activated upon coating a layer of coupled graphene oxide (GO) with sensitive chemical compounds along with gold nanostars (Au NS) that can detect the trace of viruses in any aquatic biological media (e.g., blood, saliva and oropharyngeal/nasopharyngeal swab) through interaction with active functional groups of their glycoproteins. The method do not require any extraction and/or biomarkers for detection of target viruses and can identify trace of different pathogenic viruses in about 1 min. The nanosensor also demonstrated superior limit of detection (LOD) and sensitivity of 1.68 × 10-22 µg mL-1 and 0.0048 µAµg.mL-1. cm-2, respectively, toward detection of SARS-CoV-2 in biological media, while blind clinical evaluations of 100 suspected samples furtherly confirmed the superior sensitivity/specificity of developed nanosystem toward rapid identification of ill people even at incubation and prodromal periods of illness.


Asunto(s)
Betacoronavirus/aislamiento & purificación , Técnicas de Laboratorio Clínico , Infecciones por Coronavirus/diagnóstico , Técnicas Electroquímicas/instrumentación , Neumonía Viral/diagnóstico , Glicoproteína de la Espiga del Coronavirus/análisis , Animales , Técnicas Biosensibles/instrumentación , Electrodos , Diseño de Equipo , Oro/química , Grafito/química , Humanos , Límite de Detección , Nanopartículas del Metal/química , Pandemias
20.
J Infect Chemother ; 27(1): 117-119, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32994136

RESUMEN

The novel coronavirus disease 2019 (COVID-19) is diagnosed by positive result of reverse transcription polymerase chain reaction (RT-PCR) for the novel coronavirus. We concluded that cycle threshold value (Ct-value) of real-time RT-PCR (rRT-PCR) assay could decrease as patients recover. Results of rRT-PCR assay could remain positive among asymptomatic patients for longer than 2 weeks. The discharge criteria of COVID-19 patients using a negative result of rRT-PCR should be reconsidered.


Asunto(s)
Infecciones por Coronavirus/diagnóstico , Neumonía Viral/diagnóstico , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Adolescente , Adulto , Anciano de 80 o más Años , Enfermedades Asintomáticas , Betacoronavirus/aislamiento & purificación , Técnicas de Laboratorio Clínico/métodos , Infecciones por Coronavirus/virología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nasofaringe/virología , Pandemias , Alta del Paciente , Neumonía Viral/virología , Índice de Severidad de la Enfermedad , Carga Viral , Adulto Joven
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