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1.
Artículo en Inglés | MEDLINE | ID: mdl-32011597

RESUMEN

INTRODUCTION: In 2016, Puerto Rico became the focal point of the Zika epidemic, with more than 36 000 laboratory-confirmed cases before August. The Puerto Rico Department of Health (PRDH) responded by providing tests to symptomatic and asymptomatic pregnant women. The increased demand for Zika testing placed unprecedented strain on the laboratory capacity and information management processes used within the PRDH. The PRDH recognized the need to have an updated informatics system that securely manages, stores, and transmits digital data. The Centers for Disease Control and Prevention funded the Public Health Informatics Institute to collaborate with the PRDH to assess and improve the informatics capability to respond to the ongoing Zika virus transmission in Puerto Rico. APPROACH: The team employed a 4-component approach to assess the informatics system and improve the information management processes for laboratory testing and reporting of arboviral diseases (Zika, chikungunya, and dengue). The method consisted of a (1) needs assessment, (2) business process analysis and requirements definition, (3) vendor analysis, and (4) solution implementation. RESULTS: The needs assessment determined that the PRDH's procedures for arbovirus testing and reporting were highly complex and paper-based and thus did not maximize the use of existing technology. The solution was to build a Web portal. The business process analysis yielded information to create a map of the flow of specimens, an arbovirus context diagram, and more than 200 requirements. The requirements identified in this process guided the design and creation of the Web portal. DISCUSSION: This report describes the process to build a Web portal to enhance laboratory testing and electronic reporting of Zika cases during the 2016 epidemic in Puerto Rico. We demonstrate the utility of applying the Collaborative Requirements Development Methodology, a proven informatics method, to the development of a Web portal for managing arboviruses in a health department.

2.
Cien Saude Colet ; 25(2): 567-574, 2020 Feb.
Artículo en Portugués | MEDLINE | ID: mdl-32022196

RESUMEN

The scope of this article is to analyze the concept of the Zika Virus Congenital Syndrome. It is a conceptual analysis, based on Walker and Avant. In order to operationalize the search, a systematic review was conducted. The essence of the concept of the Zika Virus Congenital Syndrome is determined by the following attributes: intracranial calcification, ventriculomegaly, and diminished brain volume. For this syndrome to occur, it is necessary to have the following antecedents: transplacental transmission of a mother infected by the bite of the Aedes SSP mosquito or by sexual contact. Accordingly, this entails a set of signs and symptoms that go beyond fetal or postnatal microcephaly, such as, for example, delayed neuropsychomotor development, auditory and visual abnormalities, craniofacial disproportion, overlapping cranial sutures, prominent occipital bone, excess nuchal skin, epilepsy, irritability, dyskinesia, hypertonia, hypotonia, hemiplegia, hemiparesis, spasticity and hyperreflexia. The concept of the Zika Virus Congenital Syndrome is newly acknowledged. The presence of the set of signs and symptoms by the Zika Virus Congenital Syndrome is determined by intracranial calcification and decreased brain volume, and the baby may present microcephaly at birth or subsequently.

3.
J Infect Dis ; 2020 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-32052024

RESUMEN

Persistence of Zika virus (ZIKV) RNA in semen is common after infection. We designed a RT-PCR assay that targets antisense ZIKV RNA (asRNA) to assess ZIKV replication competence in ZIKV RNA positive semen samples. We detected ZIKV asRNA in semen of nine of nineteen men (47.4%) diagnosed with ZIKV infection. All asRNA positive samples had high ZIKV loads (Ct-values <26) and were obtained within 21 days of symptom onset. The sensitivity of the asRNA assay for detection of ZIKV replication was higher than that of conventional virus isolation methods (47.4% vs. 21.1%, p-value 0.032).

4.
Am J Obstet Gynecol ; 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31954155

RESUMEN

BACKGROUND: Zika virus (ZIKV) infection during pregnancy can cause serious birth defects, including brain and eye abnormalities. The clinical importance of detection of ZIKV ribonucleic acid (RNA) in amniotic fluid is unknown. OBJECTIVES: To describe patterns of ZIKV RNA testing of amniotic fluid relative to other clinical specimens and to examine the association between ZIKV detection in amniotic fluid and Zika-associated birth defects. Our null hypothesis was that ZIKV detection in amniotic fluid was not associated with Zika-associated birth defects. STUDY DESIGN: We conducted a retrospective cohort analysis of women with amniotic fluid specimens submitted to Colombia's National Institute of Health as part of national ZIKV surveillance from January 2016 to January 2017. Specimens (maternal serum, amniotic fluid, cord blood, umbilical cord tissue, and placental tissue) were tested for the presence of ZIKV RNA using a singleplex or multiplex real-time reverse transcriptase-polymerase chain reaction (rRT-PCR) assay. Birth defect information was abstracted from maternal prenatal and infant birth records and reviewed by expert clinicians. Chi-square and Fisher's exact tests were used to compare the frequency of Zika-associated birth defects (defined as brain abnormalities [with or without microcephaly, but excluding neural tube defects and their associated findings] or eye abnormalities) by frequency of detection of ZIKV RNA in amniotic fluid. RESULTS: Our analysis included 128 women with amniotic fluid specimens. Seventy-five women (58%) had prenatally-collected amniotic fluid, 42 (33%) at delivery, and 11 (9%) had missing collection dates. Ninety-one women had both amniotic fluid and other clinical specimens submitted for testing, allowing for comparison across specimen types. Of those 91 women, 68 had evidence of ZIKV infection based on detection of ZIKV RNA (ZIKV+) in >1 specimen. Testing of amniotic fluid collected prenatally or at delivery identified 39 (57%) of these ZIKV infections (15 [22%] identified only in amniotic fluid), and 29 (43%) infections were identified in other specimen types and not amniotic fluid. Among women included in the analysis, 89 had pregnancy outcome information available, allowing for assessment of the presence of Zika-associated birth defects. Zika-associated birth defects were significantly (p<0.05) more common among pregnancies with ZIKV+ amniotic fluid specimens collected prenatally (19/32, 59%) than for those with no laboratory evidence of ZIKV infection in any specimen (6/23, 26%), but the proportion was similar in pregnancies with only ZIKV+ specimens other than amniotic fluid (10/23, 43%). Though Zika-associated birth defects were more common among women with any ZIKV+ amniotic fluid specimen (i.e., collected prenatally or at delivery; 21/43, 49%) than those with no laboratory evidence of ZIKV infection (6/23, 26%), this comparison did not reach statistical significance (p=0.07). CONCLUSIONS: Testing of amniotic fluid provided additional evidence for maternal diagnosis of ZIKV infection. Zika-associated birth defects were more common among women with ZIKV RNA detected in prenatal amniotic fluid specimens than women with no laboratory evidence of ZIKV infection, but similar to women with ZIKV RNA detected in other, non-amniotic fluid specimen types.

5.
Talanta ; 210: 120648, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31987197

RESUMEN

Zika virus (ZIKV) is considered an emerging infectious disease of high clinical and epidemiological relevance. The epidemiological emergency generated by the virus in Latin America and Southeast Asia in 2014 evidenced the urgent need for rapid and acute diagnostic tools. The current laboratory diagnosis of ZIKV is based on molecular and serological methods. However, molecular tools need expensive and sophisticated equipment and trained personnel; and serological detection may suffer from cross-reactivity. In this context, genosensors offer an attractive alternative for field-ready, early and accurate diagnosis of ZIKV. This work reports on the development of genosensors for the differential detection of ZIKV and its discrimination from dengue (DENV) and chikungunya (CHIKV) homologous arboviruses. We designed specific capture and signal probes by bioinformatics, and prove their specificity to amplify the target genetic material by the polymerase chain reaction (PCR). The designed biotinylated capture and digoxigenin (Dig)-labeled signal probes hybridized the target in a sandwich-type format. An anti-Dig antibody labeled with the horseradish peroxidase (HRP) enzyme allowed for both optical and electrochemical detection. The genosensors detected the ZIKV genetic material in spiked serum, urine, and saliva samples and cDNA from infected patients, discriminating them from the DENV and ZIKV genetic material. The proposed system offers a step forward to the differential diagnosis of the ZIKV, closer to the patient, very promising for diagnosis and surveillance of this rapidly emerging disease.

6.
Am J Trop Med Hyg ; 2020 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-31933462

RESUMEN

Arboviral diagnosis has been complicated throughout the tropical and subtropical Americas by the recent co-circulation of Zika virus (ZIKV), chikungunya virus (CHIKV), and dengue virus (DENV). The aim of this study was to implement a multiplex real-time RT-PCR (rRT-PCR) for ZIKV, CHIKV, and DENV in Paraguay to test patients who were clinically suspected of having dengue. We tested 110 sera from patients who presented to the Hospital de Clínicas in 2016 and had testing for DENV nonstructural protein 1 (NS1; 40 positive and 70 negative). Using a composite reference standard, we confirmed 51 dengue cases (46.4%): 38/40 NS1 positive and 13/70 NS1 negative. Chikungunya virus and ZIKV were detected in one sample each, both were DENV NS1 negative. The NS1 test demonstrated good agreement with rRT-PCR for DENV. However, multiplex rRT-PCR identified a subset of dengue cases and additional arboviral infections that would not be detected if NS1 assays are relied upon for diagnosis.

7.
Viruses ; 12(1)2020 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-31936013

RESUMEN

The aim of this study is to evaluate the performance characteristics of the LIAISON XL Zika Capture IgM II. For this purpose we tested 128 samples obtained from recent infections caused by the Zika (ZIKV; 74 samples), dengue (DENV; 10 samples), chikungunya (CHIK V; 11 samples), rubella (RUBV; 10 samples) and measles (MeV; 10 samples) viruses, as well as human parvovirus B19 (HPVB19; 13 samples). The results of the assay under evaluation are compared with those obtained from an indirect immunofluorescence (IIF) assay, and the discrepancies are resolved by considering other laboratory results (PCR and a plaque-reduction neutralization test). The LIAISON showed excellent sensitivity (100%). The specificity (91.25%) was hampered by some false-positive results in recent dengue virus, chikungunya virus, measles virus and human parvovirus B19 infections. The method evaluated is adequate, but the low specificity makes it necessary to consider the clinical and epidemiological contexts of patients, as well as other laboratory results.

8.
Int J Gynaecol Obstet ; 148 Suppl 2: 9-14, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31975394

RESUMEN

OBJECTIVE: To identify newborns with congenital Zika infection (CZI) at a maternity hospital in Salvador, Brazil, during the 2016 microcephaly outbreak. METHODS: A prospective study enrolled microcephalic and normocephalic newborns with suspected CZI between January and December 2016. Serology (immunoglobulins IgM and IgG) and quantitative reverse transcriptase polymerase chain reaction (RT-qPCR) for the Zika virus were performed. Demographic and clinical characteristics of newborns with and without microcephaly were compared. RESULTS: Of the 151 newborns enrolled, 32 (21.2%) were classified as microcephalic. The majority of these cases were born between January and May 2016. IgM and IgG Zika virus antibodies were detected in 5 (23.8%) and 17 (80.9%) microcephalic newborn blood samples, respectively. Six (24%) microcephalic newborns tested positive for Zika virus by RT-qPCR in urine or placenta samples. Thirteen (11.8%) normocephalic newborns also tested positive for Zika virus by PCR in urine, plasma, or placenta samples, while IgM antibodies against Zika were detected in 4 (4.2%) others. CONCLUSIONS: Identification of 17 normocephalic CZI cases, confirmed by IgM serology or RT-qPCR for Zika virus, provides evidence that CZI can present asymptomatically at birth. This finding highlights the need for prenatal and neonatal screening for Zika virus in endemic regions.

9.
Biosens Bioelectron ; 151: 111960, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31999574

RESUMEN

Zika virus (ZIKV) is a mosquito-borne flavivirus (FLAV) that emerged in Brazil in 2015 and has rapidly spread to more than 50 countries worldwide. However, early, accurate, and specific point-of-care (POC) diagnosis of ZIKV is very difficult because most infected patients are asymptomatic or display nonspecific symptoms similar to those of other viral infections, and most of the analysis also requires instruments. Herein, an instrument-free ZIKV POC test using a drop of blood comprising a vial immunosensor, artificial nanozyme platinum/gold core-shell nanoparticles (Pt@Au NPs) as a signal probe, and a smartphone was developed to specifically detect ZIKV without cross-reaction with other FLAVs. A high sensitivity of 1 pg/mL ZIKV, desirable specificity, data storage, and geographic location surveillance were simultaneously achieved for the proposed POC test. Our POC test suitably met the urgent needs of ports of entry, airports, and endemic regions with stressed resources, as well as strict clinical requirements for ZIKV detection.

10.
PLoS Negl Trop Dis ; 14(1): e0008039, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31995566

RESUMEN

Flaviviruses are relevant animal and human pathogens of increasing importance worldwide. The similarities of the initial clinical symptoms and the serological cross-reactivity of viral structural antigens make a laboratory diagnosis of flavivirus infection problematic. The main aim of the present study was the comparative specificity and sensitivity analysis of the non-structural protein NS1 as an antigen to detect flavivirus antibodies in sera from exposed individuals. A strategy for the purification of native recombinant non-structural protein 1 of representative flaviviruses including tick-borne encephalitis, West Nile, Zika and dengue virus was developed. The immunological properties of the purified antigens were analyzed using sera of immunized mice and of infected individuals in comparison with standard commercial assays. Recombinant NS1 protein was confirmed as a valuable option for the detection of flavivirus antibodies with reduced cross-reactivity and high sensitivity offering additional advantages for the detection of vaccine breakthrough cases.

11.
Talanta ; 208: 120338, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-31816752

RESUMEN

Arboviruses have been emerging as a significant global health problem due to the recurrent epidemics. Arboviruses require the development of new diagnostic devices due to the nonspecific clinical manifestations. Herein, we report a biosensor based on cysteine (Cys), zinc oxide nanoparticles (ZnONp), and Concanavalin A (ConA) lectin to differentiate between arboviruses infections. ConA is capable of interacting with the saccharide components of the viral capsid. In this study, we evaluated the reproducibility, sensitivity, and specificity of the sensor for the virus of Dengue type 2 (DENV2), Zika (ZIKV), Chikungunya (CHIKV), and Yellow fever (YFV). Atomic force microscopy measurements confirmed the electrode surface modification and revealed a heterogeneous topography during the biorecognition process. Cyclic voltammetry (CV) and impedance spectroscopy (EIS) were used to characterize the biosensor. The blockage of the oxidation-reduction process is related to the formation of Cys-ZnONp-ConA system on the electroactive area and its subsequent interaction with viral glycoproteins. The sensor exhibited a linear response to different concentrations of the studied arboviruses. Our study demonstrates that ConA lectin recognizes the structural glycoproteins of the DENV2, ZIKV, CHIKV, and YFV. DENV2 is the most structurally similar to ZIKV. Our results have shown that the impedimetric response correlates with the structural glycoproteins, as follow: DENV2 (18.6 kΩ) > ZIKV (14.6 kΩ) > CHIKV (6.86 kΩ) > YFV (5.98 kΩ). The homologous structural regions contribute to ConA-arboviruses recognition. Our results demonstrate the use of the proposed system for the development of biosensors for arboviruses infections.

12.
Clin Microbiol Rev ; 33(1)2019 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-31826871

RESUMEN

SUMMARYInfections during pregnancy that may cause congenital abnormalities have been recognized for decades, but their diagnosis is challenging. This was again illustrated with the emergence of Zika virus (ZIKV), highlighting the inherent difficulties in estimating the extent of pre- and postnatal ZIKV complications because of the difficulties in establishing definitive diagnoses. We reviewed the epidemiology, infection kinetics, and diagnostic methods used for Toxoplasma gondii, parvovirus B19, rubella virus, and cytomegalovirus (TORCH) infections and compared the results with current knowledge of ZIKV diagnostic assays to provide a basis for the inclusion of ZIKV in the TORCH complex evaluations. Similarities between TORCH pathogens and ZIKV support inclusion of ZIKV as an emerging TORCH infection. Our review evaluates the diagnostic performance of various TORCH diagnostic assays for maternal screening, fetal screening, and neonatal screening. We show that the sensitivity, specificity, and positive and negative predictive value of TORCH complex pathogens are widely variable, stressing the importance of confirmatory testing and the need for novel techniques for earlier and accurate diagnosis of maternal and congenital infections. In this context it is also important to acknowledge different needs and access to care for different geographic and resource settings.

13.
Sci Transl Med ; 11(522)2019 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-31826984

RESUMEN

Flaviviruses such as dengue, yellow fever, Zika, West Nile, and Japanese encephalitis virus present substantial global health burdens. New vaccines are being sought to address safety and manufacturing issues associated with current live attenuated vaccines. Here, we describe a new insect-specific flavivirus, Binjari virus, which was found to be remarkably tolerant for exchange of its structural protein genes (prME) with those of the aforementioned pathogenic vertebrate-infecting flaviviruses (VIFs). Chimeric BinJ/VIF-prME viruses remained replication defective in vertebrate cells but replicated with high efficiency in mosquito cells. Cryo-electron microscopy and monoclonal antibody binding studies illustrated that the chimeric BinJ/VIF-prME virus particles were structurally and immunologically similar to their parental VIFs. Pilot manufacturing in C6/36 cells suggests that high yields can be reached up to 109.5 cell culture infectious dose/ml or ≈7 mg/liter. BinJ/VIF-prME viruses showed utility in diagnostic (microsphere immunoassays and ELISAs using panels of human and equine sera) and vaccine applications (illustrating protection against Zika virus challenge in murine IFNAR-/- mouse models). BinJ/VIF-prME viruses thus represent a versatile, noninfectious (for vertebrate cells), high-yield technology for generating chimeric flavivirus particles with low biocontainment requirements.

14.
Cad Saude Publica ; 35(12): e00226618, 2019.
Artículo en Portugués | MEDLINE | ID: mdl-31800794

RESUMEN

This article aims to understand how parents of children with microcephaly received the diagnosis. This qualitative study was conducted at State Referral Center for Children's Neurodevelopment, Care, and Rehabilitation (NINAR) in São Luís, Maranhão State, Brazil, from April 2017 to February 2018. Participants in the study included parents or guardians of children with microcephaly. Data collection included structured and semi-structured interviews with 3 couples, 16 mothers, and 1 great-grandmother, totaling 20 interviews. The sample was defined by the saturation criterion, and content analysis was performed according to the thematic modality. Eighteen interviewees reported that the diagnosis had been disclosed to them inappropriately and traumatically, sometimes linked to a sense of "end of life" and dissociated from orientation on ways to cope with the situation and care for the child. The diagnosis of microcephaly was disclosed by physicians in 15 of the 20 cases. Three other cases were disclosed as follows: one by a nurse, one by the mother-in-law (who had learned of the diagnosis from the physician), and one by a health department employee. The other two did not receive the diagnosis: one couple learned of the microcephaly from the infant's Certificate of Life Birth and the other associated the child's problem with information broadcast on the media. Three thematic lines were analyzed: omission of the diagnosis; process of disclosure of the diagnosis; and anticipation of the prognosis. The ways diagnosis of microcephaly was disclosed to families influenced how they accepted and coped with the situation.

15.
Rev Peru Med Exp Salud Publica ; 36(3): 442-447, 2019.
Artículo en Español | MEDLINE | ID: mdl-31800936

RESUMEN

A Reverse Transcription Loop-mediated Isothermal Amplification (RT-LAMP) method was developed to detect Zika. The primers were designed based on the NS5 region of 64 complete genomes. Lyophilized LAMP reagent was used. Initially, seven different arboviruses were tested and only Zika samples tested positive. Additionally, serial dilutions of one of Zika's RNA were compared using RT-LAMP and qRT-PCR, demonstrating that RT-LAMP is 1,000 times more sensitive. We also evaluated 300 serum samples with RT-LAMP comparing the results with standard qRT-PCR methods, and we obtained a 99.3% sensitivity, 100% specificity, 100% positive predictive value, and 99.3% negative predictive value. In conclusion, this method provides a low-cost, high-performance, viable, and reliable alternative for the rapid diagnosis of Zika in primary health-care facilities.

16.
Jpn J Infect Dis ; 2019 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-31787741

RESUMEN

Oropouche Virus (OROV) is a single-stranded negative-sense RNA arbovirus transmitted to humans by the midge Culicoides paraenesis causing a disease known as Oropouche fever. In Brazil, outbreaks of the virus have been reported to be restricted to the Central-Northern region of the country. However, its incidence is underestimated mainly due to the virus clinical similarities with other arbovirus diseases including dengue (DENV), chikungunya (CHIKV), and zika (ZIKV), and the lack of specific diagnostic tests. Here, we report for the first time OROV detection in saliva and urine samples and the first cases of OROV autochthone infections in Metropolitan region of Salvador, Bahia a Northeastern capital in the coast of Brazil. Serum, saliva and urine samples negative for DENV, CHIKV, and ZIKV were tested for OROV using a RT-nested-PCR protocol in which we found two positive samples of serum, two of saliva and one of urine. This report shows the need for an efficient surveillance system to control the spread of this virus in the population and suggests the use of saliva and urine samples as an alternative for the detection of OROV when serum samples are not available.

17.
Viruses ; 12(1)2019 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-31877989

RESUMEN

The recent outbreak of Zika virus (ZIKV) in the Americas and its devastating developmental and neurological manifestations has prompted the development of field-based diagnostics that are rapid, reliable, handheld, specific, sensitive, and inexpensive. The gold standard molecular method for lab-based diagnosis of ZIKV, from either patient samples or insect vectors, is reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The method, however, is costly and requires lab-based equipment and expertise, which severely limits its use as a point-of-care (POC) tool in resource-poor settings. Moreover, given the lack of antivirals or approved vaccines for ZIKV infection, a POC diagnostic test is urgently needed for the early detection of new outbreaks and to adequately manage patients. Loop-mediated isothermal amplification (LAMP) is a compelling alternative to RT-qPCR for ZIKV and other arboviruses. This low-cost molecular system can be freeze-dried for distribution and exhibits high specificity, sensitivity, and efficiency. A growing body of evidence suggests that LAMP assays can provide greater accessibility to much-needed diagnostics for ZIKV infections, especially in developing countries where the ZIKV is now endemic. This review summarizes the different LAMP methods that have been developed for the virus and summarizes their features, advantages, and limitations.

18.
PLoS Negl Trop Dis ; 13(12): e0007988, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31877132

RESUMEN

BACKGROUND: Detecting and monitoring the transmission of arboviruses such as Zika virus (ZIKV), dengue virus, and chikungunya virus is critical for prevention and control activities. Previous work has compared the ability of different human-focused surveillance strategies to detect ZIKV transmission in U.S. counties where no known transmission had occurred, but whether virological surveillance in mosquitoes could represent an effective surveillance system is unclear. OBJECTIVES: We leveraged a unique set of data from human and virological surveillance in Ae. aegypti during the 2016 ZIKV epidemic in Caguas, Puerto Rico, to compare alternative strategies for detecting and monitoring ZIKV activity. METHODS: We developed a simulation model for mosquito and human surveillance strategies and simulated different transmission scenarios with varying infection rates and mosquito trap densities. We then calculated the expected weekly number of detected infections, the probability of detecting transmission, and the number of tests needed and compared the simulations with observed data from Caguas. RESULTS: In simulated high transmission scenarios (1 infection per 1,000 people per week), the models demonstrated that both approaches had estimated probabilities of detection of greater than 78%. In simulated low incidence scenarios, vector surveillance had higher sensitivity than human surveillance and sensitivity increased with more traps, more trapping effort, and testing. In contrast, the actual data from Caguas indicated that human virological surveillance was more sensitive than vector virological surveillance during periods of both high and low transmission. CONCLUSION: In scenarios where human surveillance is not possible or when transmission intensity is very low, virological surveillance in Ae. aegypti may be able to detect and monitor ZIKV epidemic activity. However, surveillance for humans seeking care for Zika-like symptoms likely provides an equivalent or more sensitive indicator of transmission intensity in most circumstances.

19.
Int J Infect Dis ; 2019 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-31884173

RESUMEN

OBJECTIVE: The re-emergence and spreading of tropical viruses to new areas raised worldwide a wave of concern. To treat patients in an early stage and prevent diffusion of the outbreak, an early diagnosis, and thus fast and adequate detection, is needed. To this aim, a multiplex reverse transcription real-time polymerase chain reaction TaqMan® method was designed to detect universally Zika and chikungunya viruses. DESIGN: Two methods, targeting different genome segments, were selected from literature for each virus, adapted for high genome coverage and joined into a four-plex assay which was thoroughly in-house validated. The SCREENED tool was used to evaluate the sequence coverage of the method. RESULTS: The full validation approach showed that the new four-plex method allows specific and sensitive identification and discrimination of Zika and chikungunya in routine samples. The combination of two targets per virus allowing almost 100% coverage of about 500 genomes was shown for the first time. CONCLUSION: PCR being a reliable user-friendly technique, applicable in remote areas, such multiplex methods enable early and efficient diagnosis leading to rapid treatment and effective confinement in outbreak cases as well as being an aid for surveillance and the full validation permits easy method-transfer allowing worldwide harmonization.

20.
Front Public Health ; 7: 333, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31781532

RESUMEN

Background: Zika virus (ZIKV) emerged in May 2015 in Brazil, from which it spread to many other countries in Latin America. Cases of ZIKV infection were eventually also reported in Curaçao (January 2016) and Bonaire (February 2016). Methods: In the period of 16 December 2015 until 26 April 2017, serum, EDTA-plasma or urine samples were taken at Medical Laboratory Services (MLS) from patients on Curaçao and tested in qRT-PCR at the Erasmus Medical Centre (EMC) in the Netherlands. Between 17 October 2016 until 26 April 2017 all samples of suspected ZIKV-patients collected on Curaçao, as well as on Bonaire, were tested at MLS. Paired urine and/or serum samples from patients were analyzed for ZIKV shedding kinetics, and compared in terms of sensitivity for ZIKV RNA detection. Furthermore, the age and gender of patients were used to determine ZIKV incidence rates, and their geozone location to determine the spatial distribution of ZIKV cases. Results: In total, 781 patients of 2820 tested individuals were found qRT-PCR-positive for ZIKV on Curaçao. The first two ZIKV cases were diagnosed in December 2015. A total of 112 patients of 382 individuals tested qRT-PCR-positive for ZIKV on Bonaire. For both islands, the peak number of absolute cases occurred in November 2016, with 247 qRT-PCR confirmed cases on Curaçao and 66 qRT-PCR-positive cases on Bonaire. Overall, a higher proportion of women than men was diagnosed with ZIKV on both islands, as well as mostly individuals in the age category of 25-54 years old. Furthermore, ZIKV cases were mostly clustered in the east of the island, in Willemstad. Conclusions: ZIKV cases confirmed by qRT-PCR indicate that the virus was circulating on Curaçao between at least December 2015 and March 2017, and on Bonaire between at least October 2016 and February 2017, with peak cases occurring in November 2016. The lack of preparedness of Curaçao for the ZIKV outbreak was compensated by shipping all samples to the EMC for diagnostic testing; however, both islands will need to put the right infrastructure in place to enable a rapid response to an outbreak of any new emergent virus in the future.

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