Zika Virus Diagnosis Research Articles

Disease Transmission and Diagnosis of Zika Virus.

An arbovirus belonging to the Flaviviridae family and the Flavivirus genus, the Zika virus (ZIKV), has profoundly transformed global health perception. Historically, ZIKV infections were considered infrequent, with generally mild manifestations. However, this perception changed dramatically when the virus quickly spread from Asia to the Americas, impacting many nations. It was alarming that there was a connection between ZIKV infection in pregnant women and the beginning of microcephaly in their offspring. ZIKV control and treatment are further complicated because Aedes mosquitoes, which primarily bite during the day, are the primary vectors of the virus. ZIKV diagnostic processes are complex since the virus shares symptoms with other illnesses like dengue and chikungunya. Despite the effectiveness of current diagnostic methods like real-time reverse transcription-polymerase chain reaction(RT-PCR) and enzyme-linked immunosorbent assay (ELISA), there is a clear need for more accurate antibody tests. This is especially true given that many people undergo testing while asymptomatic or after the ideal detection window. The capacity of ZIKV to infect human-derived neural progenitor cells raises worrying possibilities for severe neurological effects. With all these characteristics and their connection to birth abnormalities, research efforts into the virus's efficient treatment and prevention have increased. Overall, the emergence of ZIKV has demonstrated the necessity of a comprehensive and team-based strategy to address its myriad problems. This entails comprehending its transmission dynamics, enhancing diagnostic accuracy, and creating efficient therapies and preventive measures, all crucial to lessening the threat that ZIKV poses to the world's health.

Production and characterization of egg yolk antibodies against the ZIKV NS2B expressed in Nicotiana benthamiana

The emergence of Zika virus (ZIKV) and its associated neonatal and congenital complications pose a threat to global health, particularly in tropical and subtropical regions with co-circulation of related flaviviruses and intense vector proliferation. Diagnosis of ZIKV by RT-PCR is limited to the viraemic phase and is not always accessible in low-income tropical settings, while serological tests often show cross-reactivity with other flaviviruses. Given the similarity of ZIKV symptoms to those of other arboviruses, but the different prognosis and risks, it is important to develop specific and accessible diagnostic tools. Egg yolk antibodies (IgY) were obtained from Leghorn laying hens immunized with recombinant ZIKV NS2B protein produced in agroinfiltrated Nicotiana benthamiana. After three immunizations, total IgY was recovered from the eggs by the 20% ammonium sulfate precipitation method. After characterisation by SDS-PAGE, dot blotting and ELISA, the IgY was adsorbed to dengue virus (DENV) from cell culture supernatants and tested for its ability to specifically detect ZIKV-positive sera samples. High yield and purity were observed on SDS-PAGE for polyclonal IgY, which reacted with NS2B at high titres in ELISA and detected both NS2B and ZIKV in dot blotting. However, a cross-reaction with DENV was observed and the anti-NS2B IgY was unable to discriminate ZIKV from DENV positive sera samples, even after adsorption with DENV. This is probably due to the phylogenetic relationship of the viruses and the shared identity of their proteins.

Salivary Detection of Zika Virus Infection Using ATR-FTIR Spectroscopy Coupled with Machine Learning Algorithms and Univariate Analysis: A Proof-of-Concept Animal Study.

Zika virus (ZIKV) diagnosis is currently performed through an invasive, painful, and costly procedure using molecular biology. Consequently, the search for a non-invasive, more cost-effective, reagent-free, and sustainable method for ZIKV diagnosis is of great relevance. It is critical to prepare a global strategy for the next ZIKV outbreak given its devastating consequences, particularly in pregnant women. Attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy has been used to discriminate systemic diseases using saliva; however, the salivary diagnostic application in viral diseases is unknown. To test this hypothesis, we intradermally challenged interferon-gamma gene knockout C57/BL6 mice with ZIKV (50 µL,105 FFU, n = 7) or vehicle (50 µL, n = 8). Saliva samples were collected on day three (due to the peak of viremia) and the spleen was also harvested. Changes in the salivary spectral profile were analyzed by Student's t test (p < 0.05), multivariate analysis, and the diagnostic capacity by ROC curve. ZIKV infection was confirmed by real-time PCR of the spleen sample. The infrared spectroscopy coupled with univariate analysis suggested the vibrational mode at 1547 cm-1 as a potential candidate to discriminate ZIKV and control salivary samples. Three PCs explained 93.2% of the cumulative variance in PCA analysis and the spectrochemical analysis with LDA achieved an accuracy of 93.3%, with a specificity of 87.5% and sensitivity of 100%. The LDA-SVM analysis showed 100% discrimination between both classes. Our results suggest that ATR-FTIR applied to saliva might have high accuracy in ZIKV diagnosis with potential as a non-invasive and cost-effective diagnostic tool.

Production and Characterization of Two Specific ZIKV Antigens Based on Bioinformatic Analysis and Serological Screening

ABSTRACT Background The high structural similarity between the Zika virus (ZIKV) and other flaviviruses, such as Dengue Virus (DENV), complicates the identification of the infecting virus due to the occurrence of cross-reactions in serological assays. This phenomenon has increased the demand for more specific antigens for immunodiagnostic applications. Methods The present work aimed to identify specific regions of ZIKV and produce unique antigens through computational methods, molecular and microbiological techniques. Results Based on the computational analysis we successfully expressed two recombinant proteins derived from specific regions of the ZIKV. Through serological assays using characterized sera, we observed that the region 146–182 of ZIKV’s E protein, expressed in tandem, was not reactive despite the predictive sensitivity and specificity observed by computer analyses. On the other hand, the non-denatured fraction 220–352 of ZIKV’s NS1 showed greater specificity to IgG+ sera of ZIKV by dot blot and western blot, which highlights its properties as a possible tool in the diagnosis of ZIKV. Conclusion These findings demonstrate that ZIKV NS1 fraction 220–352 is a potential tool that may be applied in the development of serological diagnosis. We also provided data that suggest the non-applicability of the region 146–182 of ZIKV’s protein E in serological assays despite previous indications about its potential based on computational analysis.

Recent Developments in DNA-Nanotechnology-Powered Biosensors for Zika/Dengue Virus Molecular Diagnostics.

Zika virus (ZIKV) and dengue virus (DENV) are highly contagious and lethal mosquito-borne viruses. Global warming is steadily increasing the probability of ZIKV and DENV infection, and accurate diagnosis is required to control viral infections worldwide. Recently, research on biosensors for the accurate diagnosis of ZIKV and DENV has been actively conducted. Moreover, biosensor research using DNA nanotechnology is also increasing, and has many advantages compared to the existing diagnostic methods, such as polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA). As a bioreceptor, DNA can easily introduce a functional group at the 5' or 3' end, and can also be used as a folded structure, such as a DNA aptamer and DNAzyme. Instead of using ZIKV and DENV antibodies, a bioreceptor that specifically binds to viral proteins or nucleic acids has been fabricated and introduced using DNA nanotechnology. Technologies for detecting ZIKV and DENV can be broadly divided into electrochemical, electrical, and optical. In this review, advances in DNA-nanotechnology-based ZIKV and DENV detection biosensors are discussed.

Novel Therapeutic Nutrients Molecules That Protect against Zika Virus Infection with a Special Note on Palmitoleate.

Zika virus (ZIKV) is a Flavivirus from the Flaviviridae family and a positive-sense single strand RNA virus. ZIKV infection can cause a mild infection to the mother but can be vertically transmitted to the developing fetus, causing congenital anomalies. The prevalence of ZIKV infections was relatively insignificant with sporadic outbreaks in the Asian and African continents until 2006. However, recent epidemic in the Caribbean showed significant increased incidence of Congenital Zika Syndrome. ZIKV infection results in placental pathology which plays a crucial role in disease transmission from mother to fetus. Currently, there is no Food and Drug Administration (FDA) approved vaccine or therapeutic drug against ZIKV. This review article summarizes the recent advances on ZIKV transmission and diagnosis and reviews nutraceuticals which can protect against the ZIKV infection. Further, we have reviewed recent advances related to the novel therapeutic nutrient molecules that have been shown to possess activity against Zika virus infected cells. We also review the mechanism of ZIKV-induced endoplasmic reticulum and apoptosis and the protective role of palmitoleate (nutrient molecule) against ZIKV-induced ER stress and apoptosis in the placental trophoblasts.

Portable sample processing for molecular assays: application to Zika virus diagnostics.

This paper introduces a digital microfluidic (DMF) platform for portable, automated, and integrated Zika viral RNA extraction and amplification. The platform features reconfigurable DMF cartridges offering a closed, humidified environment for sample processing at elevated temperatures, as well as programmable control instrumentation with a novel thermal cycling unit regulated using a proportional integral derivative (PID) feedback loop. The system operates on 12 V DC power, which can be supplied by rechargeable battery packs for remote testing. The DMF system was optimized for an RNA processing pipeline consisting of the following steps: 1) magnetic-bead based RNA extraction from lysed plasma samples, 2) RNA clean-up, and 3) integrated, isothermal amplification of Zika RNA. The DMF pipeline was coupled to a paper-based, colorimetric cell-free protein expression assay for amplified Zika RNA mediated by toehold switch-based sensors. Blinded laboratory evaluation of Zika RNA spiked in human plasma yielded a sensitivity and specificity of 100% and 75% respectively. The platform was then transported to Recife, Brazil for evaluation with infectious Zika viruses, which were detected at the 100 PFU mL-1 level from a 5 μL sample (equivalent to an RT-qPCR cycle threshold value of 32.0), demonstrating its potential as a sample processing platform for miniaturized diagnostic testing.

A potent fluorescent biosensor integrating 3D DNA walker with localized catalytic hairpin assembly for highly sensitive and enzyme-free Zika virus detection

Zika virus (ZIKV) with worldwide distribution, high incidence and great harm, has emerged as a serious global health threat in the past few years. There is an urgent need for fast, low-cost and accurate diagnosis of ZIKV. Herein, a DNA walker integrated with localized catalytic hairpin assembly (LCHA) cascade amplification strategy is proposed as a new ZIKV assay platform satisfying the above requirements. In this strategy, the DNA walker is constructed by functionating AuNPs with locked walking strands and hairpin DNA track strands; LCHA is simply designed by fixed hairpin DNA probes H1 and H2 on a DNA tetrahedron. The target ZIKV RNA sequence initiates the DNA walker process, which generates numerous trigger sequences for activating the subsequent LCHA, generating an amplified fluorescence signal. This method allows the limit of ZIKV sequence detection down to 20 pM without enzymatic DNA amplification. Moreover, the assay can detect ZIKV from serum sample without RNA extraction, proving its practical application in biological analysis.

Development of a neutralizing antibody targeting linear epitope of the envelope protein domain III of ZIKV

Zika virus (ZIKV) infection represents an emerging infectious disease that poses an increasing threat to human health, especially after the ZIKV outbreak in Brazil in 2015. Unfortunately, there continues to be a lack of highly effective antiviral drugs or vaccines against ZIKV. In this study, we expressed the ZIKV envelope protein domain III (ZIKV EDIII) in E. coli strain BL21. The purified recombinant protein was used to immunize mice to produce monoclonal antibodies (mAbs). After 6 screening and 5 subcloning cycles, 10 monoclonal cell lines that stably produced antibodies, termed 2F5, 5B8, 6G6, 7E12, 8B6, 17E6, 19E7, 20F4, 26G6, and 37E6, were identified. The mAb 8B6 could neutralize ZIKV and recognize the ZIKV EDIII epitope (GRLITANPVITESTE). Another 9 mAbs did not exhibit neutralizing activity; however, they could specifically recognize the ZIKV EDIII and ZIKV lysate, suggesting their potential use in the diagnosis of ZIKV.

Clinical and Epidemiological Features of Acute Zika Virus Infections in León, Nicaragua

The American Zika virus (ZIKV) epidemic has highlighted the need to gain a better understanding of this emerging virus. The goal of this study was to describe the clinical symptoms, laboratory findings, and risk factors for symptomatic ZIKV infection in an area with ongoing transmission of other arboviral infections. We recruited patients at least 2 years of age seeking care at public health centers in León, Nicaragua, between January 2016 and August 2017, for fever, maculopapular rash, and/or nonsuppurative conjunctivitis with a duration of less than 1 week. A laboratory diagnosis of ZIKV was established using a combination of molecular and serological tests. Clinical and laboratory findings and potential risk factors were compared between participants with and without acute ZIKV infection. Fifty-eight (26%) of the 225 participants included in the analysis were found to have acute ZIKV infection. Pregnancy and reports of previous arboviral infection were associated with a higher risk of ZIKV infection. Rash, conjunctivitis, sore throat, and lower absolute neutrophil counts were associated with acute ZIKV infection. The clinical characteristics and risk factors identified were consistent with those identified by previous studies; however, we found sore throat to be a feature of ZIKV infection. We also found that neutrophil counts were lower in ZIKV-infected subjects. These clinical symptoms and laboratory data may help clinicians suspect ZIKV infection during future outbreaks.

Serological Differences after Acute Zika Virus Infections between Children and Adults: Implication for Use of a Serological Test.

Information is limited regarding differential serological responses after acute Zika virus (ZIKV) infections and prevalence of cross-reactivity with anti-dengue virus (DENV) assays comparing children and adults. Early convalescent sera from a cohort of suspected mild DENV cases between December 2016 and September 2018 at Bamrasnaradura Infectious Diseases Institute in Thailand were tested for nonstructural protein 1 (NS1)-based anti-ZIKV IgM and IgG ELISAs (Euroimmun), and in-house anti-DENV IgM- and IgG-capture ELISAs. ZIKV cases were identified by positive real-time reverse transcriptase-polymerase chain reaction on urine. Sera from 26 (10 children and 16 adults) ZIKV and 227 (153 children and 74 adults) non-ZIKA cases collected at the median duration of 18 days (interquartile range [IQR] 18,19) post-onset of symptoms were tested. Comparing pediatric ZIKV to adult ZIKV cases, the mean anti-ZIKV IgM ratio was higher (2.12 versus 1.27 units, respectively; P = 0.07), whereas mean anti-ZIKV IgG ratio was lower (3.13 versus 4.24 units, respectively; P = 0.03). Sensitivity of anti-ZIKV IgM and specificity of anti-ZIKV IgG in pediatric ZIKV were higher than in adult ZIKV cases (80.0% versus 43.7% and 79.1% versus 43.2%, respectively). No cross-reactivity with anti-DENV IgM- and IgG-capture ELISA were reported in pediatric ZIKV cases in our study, whereas 25% and 12.5% were found in adult ZIKV cases, respectively. Age-related ZIKV serological differences have been observed. Positive NS1-based anti-ZIKV IgM and IgG ELISA at the early convalescent phase could be useful for ZIKV diagnosis in children, even in a dengue endemic setting.

Non-structural protein 1 from Zika virus: Heterologous expression, purification, and potential for diagnosis of Zika infections

Zika virus (ZIKV) infections were associated with neurological disorders only after the Brazilian outbreak in 2015. The lack of vaccines and precise diagnosis requires a precise method to detect ZIKV infection. This study aimed to evaluate three ZIKV recombinant proteins for the development of ZIKV infections. Here, it was purified stable recombinant ZIKV Capsid (r-ZIKV-c), non-structural proteins NS1 (r-ZIKV-NS1), and NS3 (r-ZIKV-NS3) for detection of the infection by ZIKV in blood sera of patients. A commercial polyclonal antibody recognized the r-ZIKV-NS1. Here, among three proteins, NS1 showed the best result for diagnostic purposes using serum samples, despite the high similarity with NS1 from DENV, and could differentiate the infections. The recombinant NS1 was used to produce a monoclonal antibody to differentiate between DENV and ZIKV NS1. As for recombinant proteins, the result for r-ZIKV-NS1 values showed 77% and 100% sensitivity and specificity, respectively, in the IgM assay. Our data showed the protein could successfully differentiate between sera of ZIKV infected patients from sera of those not infected with the virus and differentiate from sera of DENV infected patients. Thus, the generated recombinant proteins have great potential for serological diagnosis of ZIKV in Brazil, where it is indispensable.

Engineered NS1 for Sensitive, Specific Zika Virus Diagnosis from Patient Serology.

Dengue virus (DENV) and Zika virus (ZIKV) belong to the Flaviviridae family of viruses spread by Aedes aegypti mosquitoes in tropical and subtropical areas. Accurate diagnostic tests to differentiate the 2 infections are necessary for patient management and disease control. Using characterized ZIKV and DENV patient plasma in a blind manner, we validated an ELISA and a rapid immunochromatographic test for ZIKV detection. We engineered the ZIKV nonstructural protein 1 (NS1) for sensitive serologic detection with low cross reactivity against dengue and developed monoclonal antibodies specific for the ZIKV NS1 antigen. As expected, the serologic assays performed better with convalescent than acute plasma samples; the sensitivity ranged from 71% to 88%, depending on the performance of individual tests (IgM/IgG/NS1). Although serologic tests were generally less sensitive with acute samples, our ZIKV NS1 antibodies were able to complement the serologic tests to achieve greater sensitivity for detecting early infections.

Diagnostic performance of anti-Zika virus IgM, IgAM and IgG ELISAs during co-circulation of Zika, dengue, and chikungunya viruses in Brazil and Venezuela.

BackgroundSerological diagnosis of Zika virus (ZIKV) infection is challenging because of the antibody cross-reactivity among flaviviruses. At the same time, the role of Nucleic Acid Testing (NAT) is limited by the low proportion of symptomatic infections and the low average viral load. Here, we compared the diagnostic performance of commercially available IgM, IgAM, and IgG ELISAs in sequential samples during the ZIKV and chikungunya (CHIKV) epidemics and co-circulation of dengue virus (DENV) in Brazil and Venezuela.Methodology/Principal findingsAcute (day of illness 1–5) and follow-up (day of illness ≥ 6) blood samples were collected from nine hundred and seven symptomatic patients enrolled in a prospective multicenter study between June 2012 and August 2016. Acute samples were tested by RT-PCR for ZIKV, DENV, and CHIKV. Acute and follow-up samples were tested for IgM, IgAM, and IgG antibodies to ZIKV using commercially available ELISAs. Among follow-up samples with a RT-PCR confirmed ZIKV infection, anti-ZIKV IgAM sensitivity was 93.5% (43/46), while IgM and IgG exhibited sensitivities of 30.3% (10/33) and 72% (18/25), respectively. An additional 24% (26/109) of ZIKV infections were detected via IgAM seroconversion in ZIKV/DENV/CHIKV RT-PCR negative patients. The specificity of anti-ZIKV IgM was estimated at 93% and that of IgAM at 85%.Conclusions/SignificanceOur findings exemplify the challenges of the assessment of test performance for ZIKV serological tests in the real-world setting, during co-circulation of DENV, ZIKV, and CHIKV. However, we can also demonstrate that the IgAM immunoassay exhibits superior sensitivity to detect ZIKV RT-PCR confirmed infections compared to IgG and IgM immunoassays. The IgAM assay also proves to be promising for detection of anti-ZIKV seroconversions in sequential samples, both in ZIKV PCR-positive as well as PCR-negative patients, making this a candidate assay for serological monitoring of pregnant women in future ZIKV outbreaks.

Development and validation of a one-step reverse transcription loop-mediated isothermal amplification (RT-LAMP) for rapid detection of ZIKV in patient samples from Brazil

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.

Development of cell-based colorimetric immunodetection of zika virus

Background: Zika virus (ZIKV) is a mosquito-borne flavivirus. ZIKV infection is a self-limiting febrile illness that showed symptoms that similar to those caused by other flaviviruses such as dengue virus (DENV). ZIKV infection diagnostic remains a challenge, as short viremic phase during infection makes it difficult to detect the viral components. The serologic assay, therefore, plays an important role for ZIKV diagnosis. Confirmation using Plaque Reduction Neutralization Test (PRNT) on IgM positive specimen is recommended to reduce potential false-positive results. The “gold standard” test, plaque forming assay (PFA), however, relies on formation of the cytopathic effects (CPE), which is time-consuming. In the current study, we developed a cell-based colorimetric immunodetection method or focus forming assay (FFA) for the detection and quantification of ZIKV. Methods and materials: Vero cells were seeded in a 24-well plate. ZIKV stock, diluted in 10-fold was added onto the Vero cells monolayer. After 1 h of virus adsorption, the virus inoculum was removed. Infected cells were kept at 37 °C incubator. For FFA, the cells were fixed at 2, 2.5, 3, 3.5 and 4 days after the infection. Subsequently, the cells were incubated with anti-flavivirus antibody and stained with DAB-peroxidase substrate solution. For the PFA, the cells were fixed at 3, 4, 5, 6, and 7 days after the infection. Subsequently, the cells were stained with crystal violet. Results: Microscopic evaluation of cells infected with ZIKV demonstrated that the ZIKV infection foci could be detected beginning on day 2 post-infection. In a 24-well plate format, the focus forming at 2.5 days after the infection was chosen. A complete plaque formation can be seen day-7 after the infection. The size of the plaque was huge; hence, overlapped plaques were observed in the 24 well plates. A PFA on a 6-well plate was performed and demonstrated that a 6-well plate format was more suitable to be used for PFA counting. Conclusion: Findings from the study demonstrated that both FFA and PFA were able to detect ZIKV detection. The newly developed FFA assay, however, is time-saving and suitable for higher throughput screening.

Zika Virus Disease Comparing Children and Adults in a Dengue-Endemic Setting

.Acute Zika virus (ZIKV) infection may mimic dengue virus (DENV) infection. We aimed to study the clinical difference of ZIKV disease among suspected non-severe DENV patients comparing children and adults. Patients with acute illness suspected of DENV disease plus no evidence of plasma leakage at the Bamrasnaradura Infectious Diseases Institute, Nonthaburi, Thailand, were enrolled from December 2016 to September 2018. Clinical data including DENV rapid diagnostic test (RDT) results were collected. Zika virus diagnosis was confirmed by real-time reverse transcription PCR on urine. Of 291 (180 pediatric and 111 adult) cases enrolled, 27 (10 pediatric and 17 adult) confirmed ZIKV cases were found. Rash was more frequent among pediatric ZIKV than pediatric non-ZIKV cases (100% versus 60%, P = 0.01). Rash, arthralgia, and conjunctivitis were more frequent among adult ZIKV than adult non-ZIKV cases (100% versus 29.8%, 64.7% versus 26.6%, 52.9% versus 9.7%, all P < 0.01, respectively). The median (interquartile range [IQR]) duration of rash was 4.5 (3.0, 7.25) days and 6.0 (4.5, 7.0) days in pediatric and adults ZIKV cases, respectively. Pediatric ZIKV cases had more fever (100% versus 58.5%, P = 0.03) but less arthralgia (20% versus 64.7%, P = 0.04) and less conjunctivitis (10% versus 52.9%, P = 0.04) than adult ZIKV cases. No ZIKV cases with DENV RDTs performed around day 3 of illness were positive for dengue nonstructural protein 1 (NS1) antigen. In dengue-endemic settings, rash and fever in children, and rash, arthralgia, and conjunctivitis in adults, particularly if rash persists for ≥ 3 days, plus negative dengue NS1 Ag during early febrile phase should prompt ZIKV diagnostic testing.

Accuracy of the Zika IgM Antibody Capture Enzyme-Linked Immunosorbent Assay from the Centers for Disease Control and Prevention (CDC Zika MAC-ELISA) for Diagnosis of Zika Virus Infection.

Serological diagnosis of Zika virus (ZIKV) infection is challenging because of antigenic cross-reactivity with dengue virus (DENV). This study evaluated the accuracy of the Zika IgM antibody capture enzyme-linked immunosorbent assay (CDC Zika IgM MAC-ELISA) in differentiating between ZIKV and DENV infections. To determine sensitivity, we used acute- and convalescent-phase sera from 21 patients with RT-PCR-confirmed ZIKV infection. To determine specificity, we used acute- and convalescent-phase sera from 60 RT-PCR-confirmed dengue cases and sera from 23 blood donors. During the acute-phase of the illness, the assay presented a sensitivity of 12.5% (2/16) for samples collected 0–4 days post symptoms onset (DPSO), and of 75.0% (3/4) for samples collected 5–9 DPSO. During the convalescent-phase of the illness, the test sensitivity was 90.9% (10/11), 100% (2/2), and 0% (0/2) for samples obtained 12–102, 258–260, and 722–727 DPSO, respectively. Specificity for acute- and convalescent-phase samples from RT-PCR-confirmed dengue cases was 100% and 93.2%, respectively. Specificity for blood donor samples was 100%. The assay is an accurate method for Zika serological diagnosis and proved to be reliable for use during surveillance and outbreak investigations in settings where ZIKV and DENV cocirculate.

The expanding arms of Zika virus: An updated review with recent Indian outbreaks.

Zika virus (ZIKV) outbreaks and their adverse clinical consequences have raised concerns throughout the world. ZIKV was little known during the initial outbreaks in Yap islands and French Polynesia, but it came to attention after the series of Brazil outbreaks in which severe complications like microcephaly in newborn babies was detected. During 2018, outbreaks of ZIKV occurred in two states of India which, being a tropical country, has congenial climatic conditions, abundance of highly competent mosquito vectors such as Aedes aegypti and Aedes albopictus, and an immunologically naïve population. In this review, we will briefly discuss the history, epidemiology, evolution, transmission (vector-borne and non-vector borne), pathogenesis, clinical signs and unusual presentations, laboratory diagnosis, treatment, prevention and control of ZIKV. Finally, we suggest priorities for urgent research required to address unanswered questions about Zika infections and help bring this virus under control.

Evolutions and upcoming on Zika virus diagnosis through an outbreak: A systematic review.

Zika virus (ZIKV) is an enveloped, positive single-stranded sense RNA virus transmitted by Aedes species. Many efforts have been conducted to find a good, reliable and cost-effective test for ZIKV diagnosis. Diagnosis is still imprecise, expensive and there is not a standard model. We investigated the publications on ZIKV diagnostics and analyzed varieties of diagnostic methods, sensibility, specificity, and the evolution of new methodologies. Conducted in accordance with the PRISMA-P statement, three blocks of MeSH terms were assembled: group I: virus infection; group II: diagnostic methodologies; group III: characteristics and varieties on diagnostic methods. Search was performed on PubMed, Web of Science and SCOPUS databases. Eighteen articles were retrieved, reporting serological and molecular diagnostic techniques. Serum was used as the main biological material in the serological diagnosis, but urine and sperm were presented as an alternative. Molecular methods used structural and nonstructural regions of ZIKV genome. Experimental methodologies were more efficient, faster, and cheaper. Serological tests are faster and less expensive than molecular assays, but molecular assays are more specific. The use of both methodologies would be the most appropriate and reliable way to obtain correct diagnostic results.