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1.
Biomed Microdevices ; 23(2): 24, 2021 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-33855638

RESUMEN

This article describes the fabrication of a low-cost Polymerase Chain Reaction (PCR) instrument to detect diseases. In order to reduce the instrument price and simplify construction we developed an alternative fabrication process, transforming conventional printed circuit boards (PCB) in heating elements, avoiding the use of aluminum heating/cooling blocks and Peltier devices. To cool down the reaction a simple computer fan was used. The vial holder was fabricated using two double side PCB boards assembled in a sandwich-like configuration. The bottom PCB has a resistance of 0.9 Ω used to heat the reaction mix, while the top layer has a resistance of 1.1 Ω to heat the vial body, preventing vapor condensation. The top board was maintained at ~ 110 ± 1 °C during all cycles. The final device was able to heat and cool down the reaction at rates of ~ 2.0 °C/s, a rate comparable to commercial thermocyclers. An SMD NTC thermistor was used as temperature sensors, and a PID (proportional-integral-derivative) control algorithm was implemented to acquire and precisely control the temperature. We also discuss how the instrument is calibrated. The device was tested successfully for the amplification of T. pallidum (Syphilis) bacterial DNA and Zika virus RNA samples, showing similar performance to a commercial PCR instrument.

2.
PLoS One ; 16(4): e0249602, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33793682

RESUMEN

INTRODUCTION: Early and rapid confirmation of dengue infections strengthens disease surveillance program and are critical to the success of vector control measures. Rapid diagnostics tests (RDTs) are increasingly used to confirm recent dengue infections due to their ease of use and short turnaround time for results. Several studies undertaken in dengue-endemic Southeast Asia have reported the performance of RDTs against enzyme-linked immunosorbent assay (ELISA), reverse transcriptase polymerase chain reaction (RT-PCR) and virus isolation methods. However, few studies have compared multiple RDTs for the detection of dengue NS1 antigen and IgM antibody in a single combo cassette. We evaluated six RDTs in Singapore for their utility in routine clinical testing to detect recent dengue infections. METHODS: The evaluation comprised two phases. The first phase sought to determine each RDT's specificity to dengue NS1 and IgM using zika and chikungunya virus supernatant and zika convalescent samples. RDTs that cross-reacted with zika or chikungunya were not further tested in phase 2. The second phase sought to determine the sensitivity and specificity of the remaining RDTs to dengue NS1 and IgM using pre-characterised dengue specimens and non-dengue/chikungunya febrile clinical specimens. RESULTS: None of the RDTs cross-reacted with zika IgM in Phase 1. Truquick and Quickprofile cross reacted with zika and chikungunya viruses and were not evaluated thereafter. Standard Q had the highest dengue NS1 and IgM sensitivity at 87.0% and 84.3% respectively whereas Bioline (68.5%) and Multisure (58.3%) had the lowest dengue NS1 and IgM sensitivity respectively. Combining dengue NS1/IgM detection results greatly improved the RDT ability to detect recent dengue infection; Standard Q had the highest sensitivity at 99.1% while Multisure had the lowest at 92.6%. All the RDTs were highly specific for dengue NS1 and IgM (96.7% to 100%). All the RDTs had high positive predictive values (98.4% to 100%) for NS1, IgM and combined NS1/IgM parameters whereas Standard Q had the highest negative predictive values at 68.2% (NS1), 63.8% (IgM) and 96.8% (NS1/IgM). For the RDTs, detection of NS1 declined from acute to convalescent phase of illness whereas IgM detection rate gradually increased over time. CONCLUSION: In our study, several RDTs were evaluated for their diagnostic accuracy and capability in detecting recent dengue infection. Standard Q demonstrated a high degree of diagnostic accuracy and capability in the detection of NS1 and IgM biomarkers. RDTs can provide rapid and accurate confirmation of recent dengue infections and augment dengue surveillance and control programmes. Further studies are required to assess the usefulness of these RDTs in other epidemiology settings.

3.
Microorganisms ; 9(4)2021 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-33808104

RESUMEN

COVID-19 and arboviruses (ARBOD) epidemics co-occurrence is a great concern. In tropical and subtropical regions, ARBOD diseases such as chikungunya, dengue, and Zika are frequent. In both COVID-19 and ARBOD cases, an accurate diagnosis of infected patients is crucial to promote adequate treatment and isolation measures in COVID-19 cases. Overlap of clinical symptoms and laboratory parameters between COVID-19 and ARBOD present themselves as an extra challenge during diagnosis. COVID-19 diagnosis is mainly performed by quantitative reverse polymerase chain reaction (RT-qPCR), while ARBOD diagnosis is performed by serology, detection of antigen or antibody, and molecular diagnosis. In this review, the epidemiologic profile of arboviruses and SARS-CoV-2 is analyzed, and potential risks of symptom overlap is addressed. The implementation of an analytical platform based on infrared (IR) spectroscopy, MALDI-TOF mass spectrometry, and RT-qPCR is discussed as an efficient strategy for a fast, robust, reliable, and cost-effective diagnosis system even during the co-occurrence of virus outbreaks. The spectral data of IR spectroscopy and MALDI-TOF MS obtained from COVID-19 infected and recovered patients can be used to build up an integrated spectral database. This approach can enable us to determine quickly the groups that have been exposed and have recovered from COVID-19 or ARBOD, avoiding misdiagnoses.

4.
Pathog Glob Health ; : 1-9, 2021 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-33645470

RESUMEN

Mayaro virus, which can often go undetected due to its clinical manifestations and intimate alignment with dengue and chikungunya viruses, is one of the most neglected arboviruses. The virus has been found in several outbreaks, where a moderate-to-severe and potentially incapacitating joint disease has been observed. MAYV usually circulates in a sylvan cycle of forest mosquitoes and vertebrates, causing sporadic sylvatic infections to humans, and some outbreaks in sub-urban areas. This study focuses on the demonstration of the possible co-circulation of Mayaro virus with chikungunya virus and Zika virus during the outbreaks that occurred in Trinidad and Tobago in 2014 and 2016, respectively. Acute samples from patients who previously tested negative for chikungunya, dengue, and Zika, and specifically exhibiting joint pain were selected and investigated for the presence of Mayaro virus genome using real-time RT-PCR techniques. Nine persons were shown to be positive for Mayaro virus during the chikungunya outbreak of 2014, while no one during the Zika outbreak in 2016. Five results correspond to persons living in highly urbanized areas across Trinidad. These findings provide evidence that multiple arboviral circulations are possible and could easily go undetected especially during outbreak situations. Our study is the first to demonstrate the possible co-circulation of Mayaro and chikungunya viruses and the occurrence of human cases for both diseases during an outbreak in the Caribbean. A possible change in the pattern of distribution of human cases to more urbanized areas is also discussed.

5.
Sci Rep ; 11(1): 6770, 2021 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-33762667

RESUMEN

Zika virus was responsible for the microcephaly epidemic in Brazil which began in October 2015 and brought great challenges to the scientific community and health professionals in terms of diagnosis and classification. Due to the difficulties in correctly identifying Zika cases, it is necessary to develop an automatic procedure to classify the probability of a CZS case from the clinical data. This work presents a machine learning algorithm capable of achieving this from structured and unstructured available data. The proposed algorithm reached 83% accuracy with textual information in medical records and image reports and 76% accuracy in classifying data without textual information. Therefore, the proposed algorithm has the potential to classify CZS cases in order to clarify the real effects of this epidemic, as well as to contribute to health surveillance in monitoring possible future epidemics.

6.
J Matern Fetal Neonatal Med ; : 1-7, 2021 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-33781162

RESUMEN

Zika virus (ZIKV) is a widespread flavivirus transmitted to humans through the bite of Aedes mosquitoes. The number of ZIKV cases increased significantly between 2015 and 2016, and Brazil was the first to report autochthonous transmission of infection. The main neurological disorder related to ZIKV infection is microcephaly. Fetal magnetic resonance imaging (MRI) is the gold standard examination for the analysis of fetal brain infection, followed by obstetric ultrasonography. Cerebral atrophy, intracranial calcifications, ventriculomegaly, cerebellar, and brain gyrus abnormalities are some of the most common findings. Postnatal MRI shows high sensitivity and specificity. Corpus callosum abnormalities, cerebellar hypoplasia, and choroid plexus dilation can be also observed. We present a review of congenital ZIKV infection with emphasis on pre and postnatal brain findings using ultrasonography, MRI, computed tomography, and three-dimensional reconstruction models.

7.
Biosens Bioelectron ; 180: 113112, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33706158

RESUMEN

Infectious diseases caused by viruses can elevate up to undesired pandemic conditions affecting the global population and normal life function. These in turn impact the established world economy, create jobless situations, physical, mental, emotional stress, and challenge the human survival. Therefore, timely detection, treatment, isolation and prevention of spreading the pandemic infectious diseases not beyond the originated town is critical to avoid global impairment of life (e.g., Corona virus disease - 2019, COVID-19). The objective of this review article is to emphasize the recent advancements in the electrochemical diagnostics of twelve life-threatening viruses namely - COVID-19, Middle east respiratory syndrome (MERS), Severe acute respiratory syndrome (SARS), Influenza, Hepatitis, Human immunodeficiency virus (HIV), Human papilloma virus (HPV), Zika virus, Herpes simplex virus, Chikungunya, Dengue, and Rotavirus. This review describes the design, principle, underlying rationale, receptor, and mechanistic aspects of sensor systems reported for such viruses. Electrochemical sensor systems which comprised either antibody or aptamers or direct/mediated electron transfer in the recognition matrix were explicitly segregated into separate sub-sections for critical comparison. This review emphasizes the current challenges involved in translating laboratory research to real-world device applications, future prospects and commercialization aspects of electrochemical diagnostic devices for virus detection. The background and overall progress provided in this review are expected to be insightful to the researchers in sensor field and facilitate the design and fabrication of electrochemical sensors for life-threatening viruses with broader applicability to any desired pathogens.


Asunto(s)
Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Virosis/diagnóstico , Anticuerpos Antivirales/inmunología , Humanos , Técnicas Analíticas Microfluídicas , Técnica SELEX de Producción de Aptámeros
8.
Arq. ciências saúde UNIPAR ; 25(1): 37-42, jan-abr. 2021.
Artículo en Portugués | LILACS-Express | LILACS | ID: biblio-1151406

RESUMEN

As infecções ocasionadas pelos vírus da Dengue (DENV), Zika (ZIKV) e Chikungunya (CHIKV) em gestantes são de grande preocupação pelos possíveis danos causados pelos mesmos às mães e fetos. O ZIKV está relacionado à microcefalia e outras anomalias cerebrais graves em neonatos e a infecção por CHIKV em gestantes no período intraparto pode levar à transmissão vertical, com possibilidade de agravamento no quadro do neonato. E, apesar de ainda não haver relatos de ocorrência de malformações congênitas associadas à infecção por DENV em gestantes, as mesmas são consideradas um grupo de risco, pois apresentam maiores chances de evolução para formas graves ou óbito e aumento no risco de partos prematuros decorrente da infecção materna perinatal. Neste estudo, foi realizada uma análise retrospectiva dos resultados envolvendo os vírus DENV, ZIKV e CHIKV para determinar a taxa de positividade destas arboviroses em gestantes no município de São José do Rio Preto-SP, nos anos de 2018 e 2019. Para isso, foram coletados resultados de PCR em tempo real (RT-PCR) para DENV, ZIKV e CHIKV de amostras de soro e urina obtidas de 557 gestantes com histórico de febre, bem como 93 amostras de recém-nascidos (RN). Na análise dos resultados foi verificado que o sorotipo-2 de Dengue (DENV-2) foi detectado em 106/557 correspondendo a 19% das amostras, o sorotipo-1 (DENV-1) foi detectado em apenas uma amostra e o ZIKV foi detectado em duas amostras. CHIKV não foi detectado. Não foi detectado arbovírus nas amostras de RN testadas pela técnica de RT-PCR. Quanto à idade, 40% das gestantes pertenciam à faixa etária de 25 a 32 anos, seguidas pelas faixas de 33 a 40 anos e 17 a 24 anos com percentuais de 31 e 29%, respectivamente. No período, uma gestante que estava na 13ª semana de gestação foi a óbito por DENV-2. Os resultados obtidos evidenciam a importância do diagnóstico precoce das arboviroses neste grupo, viabilizando a assistência adequada às gestantes. Nesse sentido, o monitoramento da circulação simultânea de arboviroses responsáveis por causarem complicações em gestantes e infecções congênitas deve continuar em áreas endêmicas como a de São José do Rio Preto, visando um diagnóstico materno precoce e manejo adequado de gestantes testadas positivas verificando a presença de sinais de alerta e de dengue grave.


Infections caused by Dengue (DENV), Zika (ZIKV) and Chikungunya (CHIKV) viruses in pregnant women represent great concern because of the possible damage that can be caused by these viruses to both mothers and fetuses. ZIKV is related to microcephaly and other severe brain abnormalities in neonates, while CHIKV infection in pregnant women in the intrapartum period can lead to vertical transmission, with the possibility of worsening in the neonate. And although there are no reports of congenital malformations associated with DENV infection in pregnant women, they are also considered of risk group, since they have greater probability to progress to severe forms or even death. In addition, there is an increased risk of premature childbirth. In this study, a retrospective result analysis involving DENV, ZIKV and CHIKV viruses was carried out to determine the positivity rate of those arboviruses in pregnant women in the city of São José do Rio Preto-SP, in the years 2018 and 2019. For this purpose, real-time PCR results (RT-PCR) were collected for DENV, ZIKV and CHIKV from serum and urine samples obtained from 557 pregnant women with a history of fever, as well as samples from 93 newborns (NB). Dengue serotype-2 (DENV-2) was detected in 106/557, which corresponds to 19% of the samples; dengue serotype-1 (DENV-1) was detected in only one sample, and the ZIKV was detected in two samples. CHIKV was not detected. Arboviruses were not detected in the NB samples tested by the RT-PCR technique. In relation to age groups, 40% of pregnant women were between 25 to 32 years old, followed by the groups of 33 to 40 years old, and 17 to 24 years old, with 31% and 29%, respectively. In the period, a pregnant woman who was in the 13th week of pregnancy died due to DENV-2. The results obtained emphasize the importance of the early diagnosis of arboviruses in this group, thus enabling adequate assistance to pregnant women. In this sense, the monitoring of arboviruses circulation responsible for causing complications and congenital infections in pregnant women should continue in endemic areas such as São José do Rio Preto, aiming at an early maternal diagnosis and adequate management of the patients who tested positive, checking for the presence of any alert signs and severe dengue.

9.
Med Res Rev ; 2021 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-33559917

RESUMEN

Zika virus (ZIKV) has emerged as a particularly notorious mosquito-borne flavivirus, which can lead to a devastating congenital syndrome in the fetuses of pregnant mothers (e.g., microcephaly, spasticity, craniofacial disproportion, miscarriage, and ocular abnormalities) and cause the autoimmune disorder Guillain-Barre' syndrome of adults. Due to its severity and rapid dispersal over several continents, ZIKV has been acknowledged to be a global health concern by the World Health Organization. Unfortunately, the ZIKV has recently resurged in India with the potential for devastating effects. Researchers from all around the world have worked tirelessly to develop effective detection strategies and vaccines for the prevention and control of ZIKV infection. In this review, we comprehensively summarize the most recent research into ZIKV, including the structural biology and evolution, historical overview, pathogenesis, symptoms, and transmission. We then focus on the detection strategies for ZIKV, including viral isolation, serological assays, molecular assays, sensing methods, reverse transcription loop mediated isothermal amplification, transcription-mediated amplification technology, reverse transcription strand invasion based amplification, bioplasmonic paper-based device, and reverse transcription isothermal recombinase polymerase amplification. To conclude, we examine the limitations of currently available strategies for the detection of ZIKV, and outline future opportunities and research challenges.

10.
PLoS Negl Trop Dis ; 15(2): e0009014, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33539393

RESUMEN

BACKGROUND: Chikungunya, dengue, and Zika are three different arboviruses which have similar symptoms and are a major public health issue in Colombia. Despite the mandatory reporting of these arboviruses to the National Surveillance System in Colombia (SIVIGILA), it has been reported that the system captures less than 10% of diagnosed cases in some cities. METHODOLOGY/PRINCIPAL FINDINGS: To assess the scope and degree of arboviruses reporting in Colombia between 2014-2017, we conducted an observational study of surveillance data using the capture-recapture approach in three Colombian cities. Using healthcare facility registries (capture data) and surveillance-notified cases (recapture data), we estimated the degree of reporting by clinical diagnosis. We fit robust Poisson regressions to identify predictors of reporting and estimated the predicted probability of reporting by disease and year. To account for the potential misclassification of the clinical diagnosis, we used the simulation extrapolation for misclassification (MC-SIMEX) method. A total of 266,549 registries were examined. Overall arboviruses' reporting ranged from 5.3% to 14.7% and varied in magnitude according to age and year of diagnosis. Dengue was the most notified disease (21-70%) followed by Zika (6-45%). The highest reporting rate was seen in 2016, an epidemic year. The MC-SIMEX corrected rates indicated underestimation of the reporting due to the potential misclassification bias. CONCLUSIONS: These findings reflect challenges on arboviruses' reporting, and therefore, potential challenges on the estimation of arboviral burden in Colombia and other endemic settings with similar surveillance systems.

11.
Sci Rep ; 11(1): 4111, 2021 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-33602985

RESUMEN

We have previously developed and validated a one-step assay based on reverse transcription loop-mediated isothermal amplification (RT-LAMP) for rapid detection of the Zika virus (ZIKV) from mosquito samples. Patient diagnosis of ZIKV is currently carried out in centralized laboratories using the reverse transcription-quantitative polymerase chain reaction (RT-qPCR), which, while the gold standard molecular method, has several drawbacks for use in remote and low-resource settings, such as high cost and the need of specialized equipment. Point-of-care (POC) diagnostic platforms have the potential to overcome these limitations, especially in low-resource countries where ZIKV is endemic. With this in mind, here we optimized and validated our RT-LAMP assay for rapid detection of ZIKV from patient samples. We found that the assay detected ZIKV from diverse sample types (serum, urine, saliva, and semen) in as little as 20 min, without RNA extraction. The RT-LAMP assay was highly specific and up to 100 times more sensitive than RT-qPCR. We then validated the assay using 100 patient serum samples collected from suspected cases of arbovirus infection in the state of Pernambuco, which was at the epicenter of the last Zika epidemic. Analysis of the results, in comparison to RT-qPCR, found that the ZIKV RT-LAMP assay provided sensitivity of 100%, specificity of 93.75%, and an overall accuracy of 95.00%. Taken together, the RT-LAMP assay provides a straightforward and inexpensive alternative for the diagnosis of ZIKV from patients and has the potential to increase diagnostic capacity in ZIKV-affected areas, particularly in low and middle-income countries.

12.
Micromachines (Basel) ; 12(2)2021 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-33578979

RESUMEN

The last few decades have been plagued by viral outbreaks that present some of the biggest challenges to public safety. The current coronavirus (COVID-19) disease pandemic has exponentiated these concerns. Increased research on diagnostic tools is currently being implemented in order to assist with rapid identification of the virus, as mass diagnosis and containment is the best way to prevent the outbreak of the virus. Accordingly, there is a growing urgency to establish a point-of-care device for the rapid detection of coronavirus to prevent subsequent spread. This device needs to be sensitive, selective, and exhibit rapid diagnostic capabilities. Electrochemical biosensors have demonstrated these traits and, hence, serve as promising candidates for the detection of viruses. This review summarizes the designs and features of electrochemical biosensors developed for some past and current pandemic or epidemic viruses, including influenza, HIV, Ebola, and Zika. Alongside the design, this review also discusses the detection principles, fabrication techniques, and applications of the biosensors. Finally, research and perspective of biosensors as potential detection tools for the rapid identification of SARS-CoV-2 is discussed.

13.
PLoS Negl Trop Dis ; 15(1): e0009028, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33476338

RESUMEN

BACKGROUND: Epidemic arbovirus transmission occurs among humans by mosquito bites and the sylvatic transmission cycles involving non-human primates (NHPs) still exists. However, limited data are available on the extent in NHPs infections and their role. In this study, we have developed and validated a high-throughput serological screening tool to study the circulation of multiple arboviruses that represent a significant threat to human health, in NHPs in Central Africa. METHODOLOGY/PRINCIPAL FINDINGS: Recombinant proteins NS1, envelope domain-3 (DIII) for the dengue (DENV), yellow fever (YFV), usutu (USUV), west nile (WNV) and zika (ZIKV) and envelope 2 for the chikungunya (CHIKV) and o'nyong-nyong (ONNV) were coupled to Luminex beads to detect IgG directed against these viruses. Evaluation of test performance was made using 161 human sera of known arboviral status (66 negative and 95 positive). The sensitivity and specificity of each antigen were determined by statistical methods and ROC curves (except for ONNV and USUV). All NS1 antigens (except NS1-YFV), CHIKV-E2 and WNV-DIII had sensitivities and specificities > 95%. For the other DIII antigens, the sensitivity was low, limiting the interest of their use for seroprevalence studies. Few simultaneous reactions were observed between the CHIKV+ samples and the NS1 antigens to the non-CHIKV arboviruses. On the other hand, the DENV+ samples crossed-reacted with NS1 of all the DENV serotypes (1 to 4), as well as with ZIKV, USUV and to a lesser extent with YFV. A total of 3,518 samples of 29 species of NHPs from Cameroon and the Democratic Republic of Congo (DRC) were tested against NS1 (except YFV), E2 (CHIKV/ONNV) and DIII (WNV) antigens. In monkeys (n = 2,100), the global prevalence varied between 2 and 5% for the ten antigens tested. When we stratified by monkey's biotope, the arboreal species showed the highest reactivity. In monkeys from Cameroon, the highest IgG prevalence were observed against ONNV-E2 and DENV2-NS1 with 3.95% and 3.40% respectively and in DRC, ONNV-E2 (6.63%) and WNV-NS1 (4.42%). Overall prevalence was low in apes (n = 1,418): ranging from 0% for USUV-NS1 to 2.6% for CHIKV-E2. However, a very large disparity was observed among collection site and ape species, e.g. 18% (9/40) and 8.2% (4/49) of gorillas were reactive with CHIKV-E2 or WNV-NS1, respectively in two different sites in Cameroon. CONCLUSIONS/SIGNIFICANCE: We have developed a serological assay based on Luminex technology, with high specificity and sensitivity for simultaneous detection of antibodies to 10 antigens from 6 different arboviruses. This is the first study that evaluated on a large scale the presence of antibodies to arboviruses in NHPs to evaluate their role in sylvatic cycles. The overall low prevalence (<5%) in more than 3,500 NHPs samples from Cameroon and the DRC does not allow us to affirm that NHP are reservoirs, but rather, intermediate hosts of these viruses.

14.
Mem Inst Oswaldo Cruz ; 115: e200339, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33503145

RESUMEN

We evaluated sweat, blood and urine specimens obtained from an ongoing cohort study in Brazil. Samples were collected at pre-established intervals after the initial rash presentation and tested for Zika virus (ZIKV) RNA presence by real-time reverse transcriptase polymerase chain reaction (rRT-PCR). From 254 participants with confirmed infection, ZIKV RNA was detected in the sweat of 46 individuals (18.1%). Sweat presented a median cycle threshold (Ct) of 34.74 [interquartile range (IQR) 33.44-36.04], comparable to plasma (Ct 35.96 - IQR 33.29-36.69) and higher than urine (Ct 30.78 - IQR 28.72-33.22). Concomitant detection with other specimens was observed in 33 (72%) of 46 participants who had a positive result in sweat. These findings represent an unusual and not yet investigated virus shedding through eccrine glands.


Asunto(s)
ARN Viral/genética , Sudor/virología , Infección por el Virus Zika/diagnóstico , Virus Zika/aislamiento & purificación , Adulto , Sangre/virología , Brasil/epidemiología , Estudios de Cohortes , Femenino , Humanos , Masculino , ARN Viral/clasificación , ARN Viral/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Orina/virología , Virus Zika/genética , Infección por el Virus Zika/epidemiología
15.
J Virol Methods ; 290: 114064, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33453299

RESUMEN

OBJECTIVES: We evaluated the performance of a nucleoprotein-based enzyme-linked immunosorbent assay (ELISA) for detection of IgG antibodies to SARS-CoV-2. METHODS: The ELISA was based on serum IgG reactivity to a 46-kDa protein derived from the recombinant SARS-CoV2 nucleoprotein. Assay sensitivity was assessed using serum samples from 134 COVID-19 confirmed cases obtained > 15 days after symptom onset. Specificity was determined by testing sera from 94 healthy controls. Cross-reactivity was evaluated with sera from 96 individuals with previous dengue or zika virus-confirmed infections, with 44 sera from individuals with confirmed infections to other respiratory viruses or with bacterial and fungal infections that cause pneumonia and with 40 sera negative for SARS-CoV-2 nucleoprotein by commercial ELISA kits. RESULTS: The majority of subjects were male and ≥ 60 years old. Assay sensitivity was 90.3 % (95 % confidence interval 84.1 %-94.2 %) and specificity was 97.9 % (92.6 %-99.4 %). There was no cross-reactivity with sera from individuals diagnosed with dengue, zika virus, influenza virus, rhinovirus, adenovirus, respiratory syncytial virus, seasonal coronavirus, Mycobacterium tuberculosis, Staphylococcus (S. aureus and coagulase-negative), Streptococcus pneumoniae, Klebsiella pneumoniae and the fungus Aspergillus fumigatus. The level of concordance of our test with results from commercial ELISA kits was 100 %. CONCLUSION: The nucleoprotein-based ELISA was specific for detection of IgG anti-nucleoprotein antibodies to SARS-CoV-2. It utilizes a frequently employed low expense assay protocol and is easier to perform than other currently available commercial SARS-CoV2 antibody detection tests.


Asunto(s)
/diagnóstico , Ensayo de Inmunoadsorción Enzimática , Inmunoglobulina G/sangre , /aislamiento & purificación , Adulto , Anciano , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Femenino , Humanos , Inmunoglobulina G/inmunología , Masculino , Persona de Mediana Edad , Fosfoproteínas/inmunología , Sensibilidad y Especificidad
16.
PLoS One ; 16(1): e0244601, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33497414

RESUMEN

Several commercial Zika virus (ZIKV) serology assays have been developed since the recognition of ZIKV outbreaks as a Public Health Emergency of International Concern in 2016. However, test interpretation for ZIKV serology can be challenging due to antibody cross-reactivity with other flaviviruses like dengue virus (DENV). Therefore, we sought to evaluate the performance of eight commercially available ZIKV IgM and IgG assays across three testing platforms, namely, immunochromatographic tests (ICT), ELISAs and immunofluorescence tests (IIFT). The test panel comprised of 278 samples, including acute and convalescent sera or plasma from ZIKV-confirmed, DENV-confirmed, non-ZIKV and non-DENV patients, and residual sera from healthy blood donors. The ZIKV IgM and IgG serology assays yielded higher test sensitivities of 23.5% - 97.1% among ZIKV convalescent samples as compared to 5.6% - 27.8% among ZIKV acute samples; the test specificities were 63.3% - 100% among acute and convalescent DENV, non-DENV samples. Among the ELISAs and IIFTs, the Diapro ZIKV IgM ELISA demonstrated high test sensitivity (96%) and specificity (80%) when tested on early convalescent samples, while the Euroimmun ZIKV IgG ELISA yielded the highest test specificity of 97% - 100% on samples from non-ZIKV patients and healthy blood donors. For rapid ICTs, the LumiQuick IgM rapid ICT yielded low test sensitivity, suggesting its limited utility. We showed that commercial ZIKV IgM and IgG serology assays have differing test performances, with some having moderate to high test sensitivities and specificities when used in a dengue endemic setting, although there were limitations in IgG serology.

17.
Biosens Bioelectron ; 176: 112895, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33358432

RESUMEN

This study reports on the development of a novel impedimetric immunosensor design using plant-derived antigenic glycoprotein for the detection of dengue virus (DENV) IgG antibodies. The electrochemical immunosensor platform was constructed using screen-printed carbon electrode (SPCE) modified with graphene/titanium dioxide (G/TiO2) nanocomposite to improve the electrode in terms electrochemical performance and specific surface area. A plant-derived dengue envelope domain III (EDIII) protein was used as the antigenic probe protein in this immunosensing strategy. Under optimised sensing conditions, the immunosensor demonstrated high sensitivity towards DENV IgG in a wide linear working range (62.5-2000 ng/mL), with a limit of detection of 2.81 ng/mL. The immunosensor showed high specificity for discriminating DENV IgG against antibodies of other infectious disease, including the closely related Zika virus (ZIKV). The reliability of the immunosensor in serological diagnosis was verified by challenging the immunosensor against serum samples, compared to conventional enzyme-linked immunosorbent assay (ELISA). As shown by its remarkable performance throughout the study, the devised immunosensor is proposed as a reliable and practical diagnostic tool for the serological detection of dengue in realistic applications.

18.
Rev Soc Bras Med Trop ; 53: e20190557, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33263680

RESUMEN

INTRODUCTION: Congenital infection by the Zika virus (ZIKV) is responsible for severe abnormalities in the development of the central nervous system. The aim of this study was to evaluate and compare the ability of computed tomography (CT) and magnetic resonance (MR) to detect patterns of involvement of the central nervous system in congenital ZIKV syndrome. METHODS: We retrospectively analyzed CT and MR images from 34 patients with congenital ZIKV syndrome and evaluated the differences between the two methods in detecting alterations. RESULTS: The predominant radiographic finding was a simplified gyral pattern, present in 97% of cases. The second most common finding was the presence of calcifications (94.1%), followed by ventriculomegaly (85.3%), dysgenesis of the corpus callosum (85.3%), craniofacial disproportion and redundant scalp (79.4%), complete opercular opening (79.4%), occipital prominence (44.1%), cerebellar hypoplasia (14.7%), and pontine hypoplasia (11.8%). The gyral pattern was extensively simplified in most cases, and calcifications were located predominantly at the cortical-subcortical junction. CT was able to better identify calcifications (94.1% × 88.2%), while MRI presented better spatial resolution for the characterization of gyral pattern (97% × 94.1%) and corpus callosum dysgenesis (85.3% × 79.4%). CONCLUSIONS: Although congenital ZIKV syndrome does not present pathognomonic neuroimaging findings, some aspects, such as calcifications at the cortical-subcortical junction, especially when associated with compatible clinical and laboratory findings, are suggestive of intrauterine ZIKV infection.

19.
J Venom Anim Toxins Incl Trop Dis ; 26: e20200019, 2020 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-33281886

RESUMEN

Zika virus (ZIKV), an emerging arthropod-borne virus (arbovirus) of the Flaviviridae family, is a current issue worldwide, particularly because of the congenital and neurological syndromes associated with infection by this virus. As the initial clinical symptoms of all diseases caused by this group are very similar, clinical diagnosis is difficult. Furthermore, laboratory diagnostic efforts have failed to identify specific and accurate tests for each virus of the Flaviviridae family due to the cross-reactivity of these viruses in serum samples. This situation has resulted in underreporting of the diseases caused by flaviviruses. However, many companies developed commercial diagnostic tests after the recent ZIKV outbreak. Moreover, health regulatory agencies have approved different commercial tests to extend the monitoring of ZIKV infections. Considering that a specific and sensitive diagnostic method for estimating risk and evaluating ZIKV propagation is still needed, this review aims to provide an update of the main commercially approved serological diagnostics test by the US Food and Drug Administration (FDA) and Brazilian National Health Surveillance Agency (ANVISA). Additionally, we present the technologies used for monoclonal antibody production as a tool for the development of diagnostic tests and applications of these antibodies in detecting ZIKV infections worldwide.

20.
PLoS Negl Trop Dis ; 14(12): e0008896, 2020 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-33270635

RESUMEN

Zika virus (ZIKV) is a significant global health threat due to its potential for rapid emergence and association with severe congenital malformations during infection in pregnancy. Despite the urgent need, accurate diagnosis of ZIKV infection is still a major hurdle that must be overcome. Contributing to the inaccuracy of most serologically-based diagnostic assays for ZIKV, is the substantial geographic and antigenic overlap with other flaviviruses, including the four serotypes of dengue virus (DENV). Within this study, we have utilized a novel T cell receptor (TCR) sequencing platform to distinguish between ZIKV and DENV infections. Using high-throughput TCR sequencing of lymphocytes isolated from DENV and ZIKV infected mice, we were able to develop an algorithm which could identify virus-associated TCR sequences uniquely associated with either a prior ZIKV or DENV infection in mice. Using this algorithm, we were then able to separate mice that had been exposed to ZIKV or DENV infection with 97% accuracy. Overall this study serves as a proof-of-principle that T cell receptor sequencing can be used as a diagnostic tool capable of distinguishing between closely related viruses. Our results demonstrate the potential for this innovative platform to be used to accurately diagnose Zika virus infection and potentially the next emerging pathogen(s).

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