Zika virus disease: a current review of the literature

Erp57 facilitates ZIKV-induced DNA damage via NS2B/NS3 complex formation

It is believed that DNA double-strand breaks induced by Zika virus (ZIKV) infection in pregnant women is a main reason of brain damage (e.g. microcephaly, severe brain malformation, and neuropathy) in newborn babies [1,2], but its underlying mechanism is poorly understood. In this study, we report that the depletion of ERp57, a member of the protein disulphide isomerase (PDI) family, leads to the limited production of ZIKV in nerve cells. ERp57 knockout not only suppresses viral induced reactive oxygen species (ROS) mediated host DNA damage, but also decreases apoptosis. Strikingly, DNA damage depends on ERp57-bridged complex formation of viral protein NS2B/NS3. LOC14, an ERp57 inhibitor, restricts ZIKV infection and virus-induced DNA damage. Our work reveals an important role of ERp57 in both ZIKV propagation and virus-induced DNA damage, suggesting a potential target against ZIKV infection.

Systemic and Ocular Manifestations of Arboviral Infections: A Review

PURPOSE

To provide an overview of pre-selected emerging arboviruses (arthropod-borne viruses) that cause ocular inflammation in humans.

METHODS

A comprehensive review of the literature published between 1997 and 2023 was conducted in PubMed database. We describe current insights into epidemiology, systemic and ocular manifestations, diagnosis, treatment, and prognosis of arboviral diseases including West Nile fever, Dengue fever, Chikungunya, Rift Valley fever, Zika, and Yellow fever.

RESULTS

Arboviruses refer to a group of ribonucleic acid viruses transmitted to humans by the bite of hematophagous arthropods, mainly mosquitoes. They mostly circulate in tropical and subtropical zones and pose important public health challenges worldwide because of rising incidence, expanding geographic range, and occurrence of prominent outbreaks as a result of climate change, travel, and globalization. The clinical signs associated with infection from these arboviruses are often inapparent, mild, or non-specific, but they may include serious, potentially disabling or life-threatening complications. A wide spectrum of ophthalmic manifestations has been described including conjunctival involvement, anterior uveitis, intermediate uveitis, various forms of posterior uveitis, maculopathy, optic neuropathy, and other neuro-ophthalmic manifestations. Diagnosis of arboviral diseases is confirmed with either real time polymerase chain reaction or serology. Management involves supportive care as there are currently no specific antiviral drug options. Corticosteroids are often used for the treatment of associated ocular inflammation. Most patients have a good visual prognosis, but there may be permanent visual impairment due to ocular structural complications in some. Community-based integrated mosquito management programs and personal protection measures against mosquito bites are the best ways to prevent human infection and disease.

CONCLUSION

Emerging arboviral diseases should be considered in the differential diagnosis of ocular inflammatory conditions in patients living in or returning from endemic regions. Early clinical consideration followed by confirmatory testing can limit or prevent unnecessary treatments for non-arboviral causes of ocular inflammation. Prevention of these infections is crucial.

Zika virus tropism and pathogenesis: understanding clinical impacts and transmission dynamics

The Zika virus (ZIKV) is classified within the Flavivirus genus of the Flaviviridae family and is categorized as an arbovirus. The virus was initially identified in a rhesus monkey in Uganda in 1947 and later in a human in Nigeria in 1952. Since 2007, the prevalence of the virus has been on the rise, culminating in a major outbreak in the United States (US) in 2015. During this outbreak, the adult population was severely impacted, experiencing a range of symptoms, including organ failure, microcephaly, fetal death, and Guillain-Barré syndrome (GBS). Additionally, skin rash, limb swelling, fever, headache, and heightened sensitivity are found in most adults with Zika syndrome. Although the virus can be transmitted through blood, vertical transmission from mother to child, and sexual contact, the primary way of transmission of the virus is through the Aedes mosquito. Cells such as neurons, macrophages, peripheral dendritic cells, and placental cells are among the target cells that the virus can infect. The TAM AXL receptor plays a crucial role in infection. After the virus enters the body through the bloodstream, it spreads in the body with a latent period of 3 to 12 days. Currently, there is no specific treatment or publicly available vaccine for the ZIKV. Limited laboratory testing has been conducted, and existing drugs originally designed for other pathogens have been repurposed for treatment. Given the Aedes mosquito's role as a vector and the wide geographical impact of the virus, this study aims to comprehensively investigate Zika's pathogenesis and clinical symptoms based on existing knowledge and research. By doing so, we seek to enhance our understanding of the virus and inform future prevention and treatment strategies.

Craniofacial and dental features in children aged 3-5 years with congenital Zika syndrome

OBJECTIVE

Zika virus infection has been associated to congenital zika syndrome (CZS) in newborns and is characterized by microcephaly, central/axial motor and sensory dysfunction, dysphagia among other previously described severe health complications. CZS is usually diagnosed postpartum by evident/apparent neural development problems. Although there are some reports of craniofacial/dentition development in CZS, several clinical oral aspects are still unknown. This study describes some structural and functional characteristics of facial and cranial growth and deciduous dentition in CZS-affected children.

MATERIAL AND METHODS

Some cranial, facial and dental characteristics were determined in 14 children with CZS aged 3-5 years and compared them against 12 apparently healthy children paired by age and gender.

RESULTS

Fourteen CZS cases presented microcephaly, maxillary prognathism, altered facial thirds, asymmetric pupillary line, bruxism (p = 0.006), deep and anterior open bite and distal step decidual molar relationship (p = 0.031). CZS children cannot feed by themselves and most cannot walk and have not develop coordinated and intelligible language according to their chronological age. In contrast, controls presented normal skull features, have autonomous locomotion skills, speak intelligible language, feed by themselves, presented a harmonic intermaxillary relationship and have symmetrical facial thirds.

CONCLUSION

Microcephaly, dysphagia, bruxism, mandibular retrognathia, altered facial proportions and malocclusion are the main craniofacial and oral features at CZS.

CLINICAL RELEVANCE

The complications of CZS including those related with the face and the oral cavity are still being identified. This study revealed some cranial, facial and oral features in children affected by CSZ. Interdisciplinary rehabilitation protocols must address these syndromic features that could improve children and parents living conditions.

Oral alterations in children with microcephaly associated to congenital Zika syndrome: A systematic review and meta-analyses

AIMS

To synthesize the oral alterations observed in children with microcephaly associated with congenital Zika virus syndrome (CZS), and to compare the oral alterations of these children to a normotypic healthy controls.

METHODS AND RESULTS

A search was performed in six electronic databases. Observational studies published that reported oral alterations in children with CZS were selected. Two authors independently extracted data, assessed study quality, using the Joanna Briggs Institute Critical Appraisal Checklist tools, and the certainty of evidence, using Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Twenty-one studies were included in this systematic review and meta-analysis. The pooled crude occurrence showed 88% of increased salivation (95%CI: 82%-94%), 83% of biofilm (95%CI: 75%-91%), and 73% of bruxism (95%CI: 52%-95%). Compared to normotypic controls, children with CZS-associated microcephaly had a higher chance to have difficulty in lip sealing (OR: 18.28; 95%CI: 1.42-235.91), inadequate lingual posture at rest (OR: 13.57; 95%CI: 4.24-43.44), and delayed eruption (OR: 12.92; 95%CI: 3.42-48.78), with very low certainty.

CONCLUSION

There are several oral alterations found among children with CZS-associated microcephaly. They are more prone to present some of these alterations, such as difficulty in lip sealing, although with very low certainty of evidence.

Hand-held virus concentration method using a hollow fiber filter module

A virus concentration method is required for viral vaccine manufacturing and virus-related research. However, concentration methods, such as ultracentrifugation, often require capital investment. We report a simple and easy-to-use handheld syringe method for virus concentration using a hollow fiber (HF) filter module, which can be applicable to viruses of different sizes, without incorporating any special machines or reagents. This virus concentration method does not use pumps, which might cause shear stress for virus particles; therefore, it is useful for stress-sensitive virus particles, and virus-like particles, as well as other proteins. The clarified harvest of flavivirus (Zika virus) was concentrated using an HF filter module and compared with a centrifugal ultrafiltration device (CUD) for demonstration of the HF filter method. The HF filter method achieved concentration of the virus solution in less time than the CUD. The yield comparison of the recovered virus solution indicated that recovery from the developed method was comparable to using the CUD, and infectivity was maintained throughout.•The Zika virus was concentrated from 200 mL to 5 mL within 45 min using the HF filter and handheld syringe module method.•The handheld HF filter method may be applicable to stress-sensitive viruses and proteins of different sizes.•The virus concentration process should be conducted in a safety cabinet, which is preferred for virus containment.

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.

Pathogenesis and Manifestations of Zika Virus-Associated Ocular Diseases

Zika virus (ZIKV) is mosquito-borne flavivirus that caused a significant public health concern in French Polynesia and South America. The two major complications that gained the most media attention during the ZIKV outbreak were Guillain-Barré syndrome (GBS) and microcephaly in newborn infants. The two modes of ZIKV transmission are the vector-borne and non-vector borne modes of transmission. Aedes aegypti and Aedes albopictus are the most important vectors of ZIKV. ZIKV binds to surface receptors on permissive cells that support infection and replication, such as neural progenitor cells, dendritic cells, dermal fibroblasts, retinal pigment epithelial cells, endothelial cells, macrophages, epidermal keratinocytes, and trophoblasts to cause infection. The innate immune response to ZIKV infection is mediated by interferons and natural killer cells, whereas the adaptive immune response is mediated by CD8⁺T cells, Th1 cells, and neutralizing antibodies. The non-structural proteins of ZIKV, such as non-structural protein 5, are involved in the evasion of the host's immune defense mechanisms. Ocular manifestations of ZIKV arise from the virus' ability to cross both the blood-brain barrier and blood-retinal barrier, as well as the blood-aqueous barrier. Most notably, this results in the development of GBS, a rare neurological complication in acute ZIKV infection. This can yield ocular symptoms and signs. Additionally, infants to whom ZIKV is transmitted congenitally develop congenital Zika syndrome (CZS). The ocular manifestations are widely variable, and include nonpurulent conjunctivitis, anterior uveitis, keratitis, trabeculitis, congenital glaucoma, microphthalmia, hypoplastic optic disc, and optic nerve pallor. There are currently no FDA approved therapeutic agents for treating ZIKV infections and, as such, a meticulous ocular examination is an important aspect of the diagnosis. This review utilized several published articles regarding the ocular findings of ZIKV, antiviral immune responses to ZIKV infection, and the pathogenesis of ocular manifestations in individuals with ZIKV infection. This review summarizes the current knowledge on the viral immunology of ZIKV, interactions between ZIKV and the host's immune defense mechanism, pathological mechanisms, as well as anterior and posterior segment findings associated with ZIKV infection.

Modulating Neurological Complications of Emerging Infectious Diseases: Mechanistic Approaches to Candidate Phytochemicals

Growing studies are revealing the critical manifestations of influenza, dengue virus (DENV) infection, Zika virus (ZIKV) disease, and Ebola virus disease (EVD) as emerging infectious diseases. However, their corresponding mechanisms of major complications headed for neuronal dysfunction are not entirely understood. From the mechanistic point of view, inflammatory/oxidative mediators are activated during emerging infectious diseases towards less cell migration, neurogenesis impairment, and neuronal death. Accordingly, the virus life cycle and associated enzymes, as well as host receptors, cytokine storm, and multiple signaling mediators, are the leading players of emerging infectious diseases. Consequently, chemokines, interleukins, interferons, carbohydrate molecules, toll-like receptors (TLRs), and tyrosine kinases are leading orchestrates of peripheral and central complications which are in near interconnections. Some of the resulting neuronal manifestations have attracted much attention, including inflammatory polyneuropathy, encephalopathy, meningitis, myelitis, stroke, Guillain-Barré syndrome (GBS), radiculomyelitis, meningoencephalitis, memory loss, headaches, cranial nerve abnormalities, tremor, and seizure. The complex pathophysiological mechanism behind the aforementioned complications urges the need for finding multi-target agents with higher efficacy and lower side effects. In recent decades, the natural kingdom has been highlighted as promising neuroprotective natural products in modulating several dysregulated signaling pathways/mediators. The present study provides neuronal manifestations of some emerging infectious diseases and underlying pathophysiological mechanisms. Besides, a mechanistic-based strategy is developed to introduce candidate natural products as promising multi-target agents in combating major dysregulated pathways towards neuroprotection in influenza, DENV infection, ZIKV disease, and EVD.

An Integrated View of Virus-Triggered Cellular Plasticity Using Boolean Networks

Virus-related mortality and morbidity are due to cell/tissue damage caused by replicative pressure and resource exhaustion, e.g., HBV or HIV; exaggerated immune responses, e.g., SARS-CoV-2; and cancer, e.g., EBV or HPV. In this context, oncogenic and other types of viruses drive genetic and epigenetic changes that expand the tumorigenic program, including modifications to the ability of cancer cells to migrate. The best-characterized group of changes is collectively known as the epithelial–mesenchymal transition, or EMT. This is a complex phenomenon classically described using biochemistry, cell biology and genetics. However, these methods require enormous, often slow, efforts to identify and validate novel therapeutic targets. Systems biology can complement and accelerate discoveries in this field. One example of such an approach is Boolean networks, which make complex biological problems tractable by modeling data (“nodes”) connected by logical operators. Here, we focus on virus-induced cellular plasticity and cell reprogramming in mammals, and how Boolean networks could provide novel insights into the ability of some viruses to trigger uncontrolled cell proliferation and EMT, two key hallmarks of cancer.

Vector competence of Aedes aegypti and screening for differentially expressed microRNAs exposed to Zika virus

Background

Zika virus (ZIKV) is transmitted to humans primarily by Aedes aegypti. Previous studies on Ae. aegypti from Jiegao (JG) and Mengding (MD) in Yunnan province, China have shown that these mosquitoes are able to transmit ZIKV to their offspring through vertical transmission, indicating that these two Ae. aegypti strains pose a potential risk for ZIKV transmission. However, the vector competence of these two Ae. aegypti strains to ZIKV has not been evaluated and the molecular mechanisms influencing vector competence are still unclear.

Methods

Aedes aegypti mosquitoes from JG and MD were orally infected with ZIKV, and the infection rate (IR), dissemination rate (DR), transmission rate (TR) and transmission efficiency (TE) of these two mosquito strains were explored to evaluate their vector competence to ZIKV. On 2, 4 and 6 days post-infection (dpi), the small RNA profiles between ZIKV-infected and non-infected Ae. aegypti midgut and salivary gland tissues were compared to gain insights into the molecular interactions between ZIKV and Ae. aegypti.

Results

There were no significant differences in the IR, DR, TR and TE between the two Ae. aegypti strains (P > 0.05). However, ZIKV RNA appeared 2 days earlier in saliva of the JG strain, which indicated a higher competence of the JG strain to transmit ZIKV. Significant differences in the microRNA (miRNA) expression profiles between ZIKV-infected and non-infected Ae. aegypti were found in the 2-dpi libraries of both the midgut and salivary gland tissues from the two strains. In addition, 27 and 74 miRNAs (|log2 fold change| > 2) were selected from the miRNA expression profiles of ZIKV-infected and non-infected midgut and salivary gland tissues from the JG and MD strains, respectively.

Conclusions

Our results provide novel insights into the ZIKV–mosquito interactions and build a foundation for future research on how miRNAs regulate the vector competence of mosquitoes to this arbovirus.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13071-021-05007-7.

Language delay was associated with a smaller head circumference at birth in asymptomatic infants prenatally exposed to the Zika virus

AIM

Our aim was to analyse 12-month outcomes of children who were prenatally exposed to the Zika virus and asymptomatic at birth.

METHODS

This was an observational, exploratory study of infants exposed to the Zika virus during gestation and born between March 2016 and April 2017 without congenital Zika syndrome. They were followed until the age of 22 months. The outcome measure was neurodevelopment at 12 months of life, which was evaluated with the Bayley Scales of Infant and Toddler Development, Third edition (Bayley-III). The scores were adjusted for maternal education and prematurity.

RESULTS

A total of 96 infants were included in the study and 35.4% scored below the normal range in at least one Bayley-III domain. The majority (91.2%) of the infants with delayed scores presented with language delay, which was not associated with the gestational age at exposure. Receptive language was more affected by exposure than expressive language (27.0% vs 19.8%). There was a direct, and significant, association between the head circumference Z-score at birth and language delay.

CONCLUSION

Language delay was associated with a smaller head circumference at birth in infants prenatally exposed to the Zika virus and born asymptomatic. This may indicate future learning difficulties.

Role of plasmonics in detection of deadliest viruses: a review

Viruses have threatened animal and human lives since a long time ago all over the world. Some of these tiny particles have caused disastrous pandemics that killed a large number of people with subsequent economic downturns. In addition, the quarantine situation itself encounters the challenges like the deficiency in the online educational system, psychiatric problems and poor international relations. Although viruses have a rather simple protein structure, they have structural heterogeneity with a high tendency to mutation that impedes their study. On top of the breadth of such worldwide worrying issues, there are profound scientific gaps, and several unanswered questions, like lack of vaccines or antivirals to combat these pathogens. Various detection techniques like the nucleic acid test, immunoassay, and microscopy have been developed; however, there is a tradeoff between their advantages and disadvantages like safety in sample collecting, invasiveness, sensitivity, response time, etc. One of the highly resolved techniques that can provide early-stage detection with fast experiment duration is plasmonics. This optical technique has the capability to detect viral proteins and genomes at the early stage via highly sensitive interaction between the biological target and the plasmonic chip. The efficiency of this technique could be proved using commercialized techniques like reverse transcription polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) techniques. In this study, we aim to review the role of plasmonic technique in the detection of 11 deadliest viruses besides 2 common genital viruses for the human being. This is a rapidly moving topic of research, and a review article that encompasses the current findings may be useful for guiding strategies to deal with the pandemics. By investigating the potential aspects of this technique, we hope that this study could open new avenues toward the application of point-of-care techniques for virus detection at early stage that may inhibit the progressively hygienic threats.

Recent progresses and remaining challenges for the detection of Zika virus

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.

Evaluation of the frequency of neuroimaging findings in congenital infection by Zika virus and differences between computed tomography and magnetic resonance imaging in the detection of alterations

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.

Speech-language disorders in children with congenital Zika virus syndrome: A systematic review

INTRODUCTION

Having verified the true association between the Zika virus and the occurrence of microcephaly, studies were conducted to evaluate the effects of the infection on fetal development. Congenital Zika virus syndrome is a currently known condition but little addressed regarding speech, language, and hearing disorders in children.

OBJECTIVE

To conduct a systematic review of speech, language, and hearing disorders in children with congenital Zika virus syndrome.

METHODS

This systematic review followed the PRISMA instructions and the Joanna Briggs Institute guidelines, and it was registered in PROSPERO (CRD42018111764). The databases consulted were Cochrane, SciELO, PubMed, LILACS, Scopus, Web of Science, and ScienceDirect. OpenGrey and OpenThesis were used to partially capture the "grey literature". Observational studies of children with microcephaly due to congenital Zika virus syndrome were included. The risk of bias was analyzed using the 2017 Joanna Briggs Institute.

RESULTS

707 records were obtained and, after excluding the duplicates, 644 studies remained. After applying the inclusion criteria, 24 articles were considered eligible. Children with congenital Zika virus syndrome presented abnormal persistence of primitive reflexes (94.7%), impaired cognitive development (95.1%), delayed neuropsychomotor development (between 92.8 and 100%), hypertonia (between 74.7% and 90.1%), impaired language development (between 68.42% and 100%), retrognathia (38.6%), craniofacial disproportion (between 32.9% and 95.8%), altered tongue frenulum (between 30% and 36.36%), the absence of stapedial reflexes (27.3%), dysphagia (between 14% and 88.9%), and hearing changes (between 5.8% and 68.42%).

CONCLUSION

Children with congenital Zika virus syndrome may have speech, language, and hearing disorders such as hearing loss, dysphagia, alteration in the tongue frenulum, and delays in neuropsychomotor and language development.

Immuno-informatics-based identification of novel potential B cell and T cell epitopes to fight Zika virus infections

BACKGROUND

Globally, the recent outbreak of Zika virus (ZIKV) in Brazil, Asia Pacific, and other countries highlighted the unmet medical needs. Currently, there are neither effective vaccines nor therapeutics available to prevent or treat ZIKV infection.

OBJECTIVE

In this study, we aimed to design an epitope-based vaccine for ZIKV using an in silico approach to predict and analyze B- and T-cell epitopes.

METHODS

The prediction of the most antigenic epitopes has targeted the capsid and the envelope proteins as well as nonstructural proteins NS5 and NS3 using immune-informatics tools PROTPARAM, CFSSP, PSIPRED, and Vaxijen v2.0. B and T-cell epitopes were predicted using ABCpred, IEDB, TepiTool, and their toxicity were evaluated using ToxinPred. The 3-dimensional epitope structures were generated by PEP-FOLD. Energy minimization was performed using Swiss-Pdb Viewer, and molecular docking was conducted using PatchDock and FireDock server.

RESULTS

As a result, we predicted 307 epitopes of MHCI (major histocompatibility complex class I) and 102 epitopes of MHCII (major histocompatibility complex class II). Based on immunogenicity and antigenicity scores, we identified the four most antigenic MHC I epitopes: MVLAILAFLR (HLA-A*68 :01), ETLHGTVTV (HLA-A*68 :02), DENHPYRTW (HLA-B*44 :02),QEGVFHTMW (HLA-B*44 :03) and TASGRVIEEW (HLA-B*58:01), and MHC II epitopes: IIKKFKKDLAAMLRI (HLA-DRB3*02 :02), ENSKMMLELDPPFGD (HLA-DRB3*01:01), HAETWFFDENHPYRT (HLA-DRB3*01:01), TDGVYRVMTRRLLGS (HLA-DRB1*11 :01), and DGCWYGMEIRPRKEP (HLA-DRB5*01:01).

CONCLUSION

This study provides novel potential B cell and T cell epitopes to fight Zika virus infections and may prompt further development of vaccines against ZIKV and other emerging infectious diseases. However, further investigations for protective immune response by in vitro and in vivo studies to ratify the immunogenicity, safety of the predicted structure, and ultimately the vaccine properties to prevent ZIKV infections are warranted.

Association Between Antenatal Exposure to Zika Virus and Anatomical and Neurodevelopmental Abnormalities in Children

IMPORTANCE

Zika virus (ZIKV) is a mosquito-borne flavivirus recognized as teratogenic since the 2015 to 2016 epidemic. Antenatal ZIKV exposure causes brain anomalies, yet the full spectrum has not been delineated.

OBJECTIVE

To characterize the clinical features of ZIKV infection at a pediatric referral center in Rio de Janeiro, Brazil, among children with antenatal ZIKV exposure.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study conducted from May to July 2019 of a prospective cohort of 296 infants with antenatal ZIKV exposure followed up since December 2015 at a tertiary maternity-pediatric hospital.

EXPOSURES

Zika virus infection during pregnancy.

MAIN OUTCOMES AND MEASURES

Characterization of clinical features with anthropometric, neurologic, cardiologic, ophthalmologic, audiometric, and neuroimaging evaluations in infancy and neurodevelopmental assessments (Bayley Scales of Infant and Toddler Development, Third Edition) from 6 to 42 months of age, stratified by head circumference at birth (head circumference within the reference range, or normocephaly [NC] vs microcephaly [MC]).

RESULTS

Antenatal exposure to ZIKV was confirmed for 219 of 296 children (74.0%) referred to Instituto Fernandes Figueira with suspected ZIKV infection through positive maternal or neonatal polymerase chain reaction analysis or IgM serology results. Of these children, 110 (50.2%) were boys, ages ranged from 0 to 4 years, and 53 (24.2%) had congenital microcephaly. The anomalies observed in ZIKV-exposed children with MC or NC were failure to thrive (MC: 38 of 53 [71.7%]; NC: 73 of 143 [51.0%]), cardiac malformations (MC: 19 of 46 [41.3%]; NC: 20 of 100 [20.0%]), excess nuchal skin (MC: 16 of 22 [72.7%]; NC: 35 of 93 [37.6%]), auditory abnormalities (MC: 13 of 50 [26.0%]; NC: 14 of 141 [9.9%]), and eye abnormalities (MC: 42 of 53 [79.2%]; NC: 28 of 158 [17.7%]). Although they experienced fewer neurologic abnormalities than children born with MC, those with NC also had frequent neurologic abnormalities (109 of 160 [68.1%]), including hyperreflexia (36 of 136 [26.5%]), abnormal tone (53 of 137 [38.7%]), congenital neuromotor signs (39 of 93 [41.9%]), feeding difficulties (15 of 143 [10.5%]), and abnormal brain imaging results (44 of 150 [29.3%]). Among 112 children with NC with Bayley-III evaluations, 72 (64.3%) had average or above-average scores; 30 (26.8%) scored 1 SD below average in at least 1 domain; and 10 (8.9%) scored 2 SD below average in at least 1 domain. Among 112 children with NC, a smaller head circumference at birth was significantly associated with subsequent below-average cognitive scores (U = 499.5; z = -2.833; P = .004) and language scores (U = 235.5; z = -2.491; P = .01).

CONCLUSIONS AND RELEVANCE

Children without MC who were exposed to ZIKV in utero had a high frequency of anatomical and neurodevelopmental abnormalities. The head circumference at birth for children with NC was associated with neurocognitive development. Recognition of the wide spectrum of clinical phenotypes is critical to ensure early referral to rehabilitative interventions.

The Potential Economic Value of a Zika Vaccine for a Woman of Childbearing Age

INTRODUCTION

With Zika vaccine candidates under development and women of childbearing age being the primary target population, now is the time to map the vaccine (e.g., efficacy and duration of protection) and vaccination (e.g., cost) characteristic thresholds at which vaccination becomes cost effective, highly cost effective, and cost saving.

METHODS

A Markov model was developed (to represent 2019 circumstances, US$ and INT$, Region of the Americas) to simulate a woman of childbearing age and the potential risk and clinical course of a Zika infection.

RESULTS

Compared with no vaccination, vaccination was cost effective (incremental cost-effectiveness ratio: US$1,254-$82,900/disability-adjusted life years averted) when the risk of infection was ≥0.05%-0.08% (varying with country income), vaccine efficacy was ≥25%, and vaccination cost was US$1-$7,500 (INT$5-$10,000 depending on country income level). Vaccination was dominant (i.e., saved costs and provided beneficial health effects) when the infection risk was ≥0.1% for a vaccine efficacy ≥75% and when the infection risk was ≥0.5% for a vaccine efficacy ≥25%, for scenarios where vaccination conferred a 1-year duration of protection and cost ≤$200. In some cases, the vaccine was cost effective when the risk was as low as 0.015%, the cost was as high as $7,500 (INT$10,000), the efficacy was as low as 25%, and the duration of protection was 1 year.

CONCLUSIONS

The thresholds at which vaccination becomes cost effective and cost saving can provide targets for Zika vaccine development and implementation.

The Role of the Middle East in ZIKA Virus Circulation: Implications of a Cross-Sectional Study in Jordan

ZIKA virus (ZIKAV) outbreak in Latin America was associated with international concerns of ZIKAV circulation. The lack of vaccine and Food and Drug Administration (FDA)-approved drugs against this virus rendered prevention as the single most effective method to control its spread. Hence, this study aimed to assess Jordanian population knowledge, attitude, and practices toward ZIKAV and its prevention. An anonymous questionnaire was administered to adults in Amman, Jordan. The overall knowledge of participants was poor (mean knowledge score of 13.7/32). Between 75% and 86% of the respondents did not know the highest risk group of ZIKAV infection, its complications, and the major routes of transmission. About 40% of the population did not know that ZIKAV is sexually transmitted. Only 40% of the population believed that prevention measures are effective. Female gender, working in the medical field, having children, and the source of medical information were associated with significantly higher level of knowledge (R ² = 0.143, P-value < 0.0001). Being pregnant, however, was not associated with a significantly high knowledge score. Physician recommendations and government's role were the most important predictors of practices toward ZIKAV prevention. Of the 14 returnees from outbreak areas, only six were tested for ZIKAV on coming back and only three continued the use of prevention measures for a sufficient time. Therefore, formulation of a national health policy, preparedness plans against any potential transmission, and organization of educational campaigns to meet the population's health educational needs are required. Special emphasis should be placed on pregnant women and travelers to/returnees from ZIKAV-affected areas.

Zika virus infection: A correlation between prenatal ultrasonographic and postmortem neuropathologic changes

This study presents a correlation between prenatal ultrasonographic images and neuropathologic findings of postmortem tissue samples from five confirmed cases of perinatal Zika virus (ZIKV) infection belonging to the cohort of the ZEN Initiative in Bucaramanga, Colombia. Deaths occurred between June 2016 and March 2017. Mothers consulted with ZIKV infection clinical manifestations or fetal central nervous system (CNS) abnormalities or both. A detailed ultrasound scan and neurosonographic protocol was performed by maternal fetal specialists. Perinatal autopsies were performed following the Colombian National Health Institute's ZIKV protocol. The autopsies were from two fetal deaths, and three early neonatal deaths. Gestational age was between 26^2/7 and 38^2/7 weeks. Two cases were classified as mild microcephaly. Few findings by ultrasound and pathology were found in case 1 because it was a late infection; the other cases presented findings corresponding to congenital Zika syndrome: craniofacial malformations, cerebellar hypoplasia, anomalies of the corpus callosum and ventriculomegaly, all confirmed in autopsy specimens. By ultrasonography, hyperechogenicities were seen in several brain structures, which correspond to cortical and periventricular calcifications, subependymal glial reactivity and perivascular rings. The ultrasound and pathological findings show a wide spectrum of CNS anomalies that confirm the neurotropic effect of the ZIKV, recognizing the neuroimaging findings of this disease (unilateral ventriculomegaly, alterations in the corpus callosum and cerebellum, and calcifications) are highly suggestive of ZIKV infection.

Congenital Zika Syndrome in a Brazil-Paraguay-Bolivia border region: Clinical features of cases diagnosed between 2015 and 2018

Congenital Zika Syndrome (CZS) is a unique pattern of congenital abnormalities found in fetuses and neonates infected with the Zika virus (ZIKV). Here, we clinically identify and characterize infants with CZS between 2015 and 2018 in Mato Grosso do Sul, Brazil-a border area with Paraguay and Bolivia. This cross-sectional study, based on primary and secondary data, tracks the cases registered in the Brazilian Public Health Reporting System through the following stages: (1) preliminary data analysis, (2) identification of the congenital syndrome cases, (3) etiologic classification of the cases, (4) active search, and (5) clinical assessment. Of the 72 investigated cases, 16 were probable cases of CZS. Of these, it was only possible to clinically assess 11 infants. Considering the 16 probable cases of CZS, nine were classified as confirmed cases, and five as potential cases of the syndrome. Regarding clinical features, brain palsy was identified in all analyzed infants. Moreover, microcephaly and pseudobulbar syndrome were found in eight infants, and hydrocephalus was found in three individuals. In addition to these conditions, seven children were malnourished. Our study may provide significant insights for other researches that aim to elucidate CZS and its clinical and populational consequences.

Travelers to U.S.: Zika Virus Knowledge, Attitudes, and Determinants of Practices in the Middle East-Insights for Future Awareness Campaigns

Travelers act as sentinels for the spread of Zika virus. Imported Zika cases and the presence of Zika virus-transmitting mosquitoes have been documented in the Middle East. However, data on travelers’ knowledge, attitude and practices regarding Zika and its prevention measures within the Middle East are scarce. This study aimed to address this issue in a sample of Jordanian and non-Jordanian travelers to U.S. in Jordan. A paper-based questionnaire was distributed to 301 travelers to U.S. in Queen Alia International airport, Amman, Jordan. Only 2.7% of the travelers knew that Zika is associated with birth defects. A total of 10.4% of the participants knew that the bite of infected mosquitoes is a route of Zika transmission. Only 12.6% of respondents correctly identified Zika prevention measures. The level of education and future plans for pregnancy were significantly associated with a high knowledge score (R² = 0.140, p-value < 0.005). Although 76.2% of the travelers perceived Zika as a health threat, only 11.2% believed in the efficacy of the prevention measures. Formulation of educational campaigns within Middle Eastern countries and development of awareness strategies regarding Zika and its prevention within the airports are required. This is particularly essential with the upcoming 2022 FIFA World Cup in Qatar.

Development of a direct reverse-transcription quantitative PCR (dirRT-qPCR) assay for clinical Zika diagnosis

OBJECTIVE

The nucleic acid-based polymerase chain reaction (PCR) assay is commonly applied to detect infection with Zika virus (ZIKV). However, the time- and labor-intensive sample pretreatment required to remove inhibitors that cause false-negative results in clinical samples is impractical for use in resource-limited areas. The aim was to develop a direct reverse-transcription quantitative PCR (dirRT-qPCR) assay for ZIKV diagnosis directly from clinical samples.

METHODS

The combination of inhibitor-tolerant polymerases, polymerase enhancers, and dirRT-qPCR conditions was optimized for various clinical samples including blood and serum. Sensitivity was evaluated with standard DNA spiked in simulated samples. Specificity was evaluated using clinical specimens of other infections such as dengue virus and chikungunya virus.

RESULTS

High specificity and sensitivity were achieved, and the limit of detection (LOD) of the assay was 9.5×10¹ ZIKV RNA copies/reaction. The on-site clinical diagnosis of ZIKV required a 5μl sample and the diagnosis could be completed within 2h.

CONCLUSIONS

This robust dirRT-qPCR assay shows a high potential for point-of-care diagnosis, and the primer-probe combinations can also be extended for other viral detection. It realizes the goal of large-scale on-site screening for viral infections and could be used for early diagnosis and the prevention and control of viral outbreaks.

Vector competence of Australian Aedes aegypti and Aedes albopictus for an epidemic strain of Zika virus

BACKGROUND

Recent epidemics of Zika virus (ZIKV) in the Pacific and the Americas have highlighted its potential as an emerging pathogen of global importance. Both Aedes (Ae.) aegypti and Ae. albopictus are known to transmit ZIKV but variable vector competence has been observed between mosquito populations from different geographical regions and different virus strains. Since Australia remains at risk of ZIKV introduction, we evaluated the vector competence of local Ae. aegypti and Ae. albopictus for a Brazilian epidemic ZIKV strain. In addition, we evaluated the impact of daily temperature fluctuations around a mean of 28°C on ZIKV transmission and extrinsic incubation period.

METHODOLOGY/PRINCIPAL FINDINGS

Mosquitoes were orally challenged with a Brazilian ZIKV strain (8.8 log CCID50/ml) and maintained at either 28°C constant or fluctuating temperature conditions. At 3, 7 and 14 days post-infection (dpi), ZIKV RNA copies were quantified in mosquito bodies, as well as wings and legs, using qRT-PCR, while virus antigen in saliva (a proxy for transmission) was detected using a cell culture ELISA. Despite high body and disseminated infection rates in both vectors, the transmission rates of ZIKV in saliva of Ae. aegypti (50-60%) were significantly higher than in Ae. albopictus (10%) at 14 dpi. Both species supported a high viral load in bodies, with no significant differences between constant and fluctuating temperature conditions. However, a significant difference in viral load in wings and legs between species was observed, with higher titres in Ae. aegypti maintained at constant temperature conditions. For ZIKV transmission to occur in Ae. aegypti, a disseminated virus load threshold of 7.59 log10 copies had to be reached.

CONCLUSIONS/SIGNIFICANCE

Australian Ae. aegypti are better able to transmit a Brazilian ZIKV strain than Ae. albopictus. The results are in agreement with the global consensus that Ae. aegypti is the major vector of ZIKV.

Zika transmission patterns: a meta-review

OBJECTIVE

To assesses what is known and identify knowledge gaps for Zika virus (ZIKV) transmission patterns.

METHODS

Meta-review searching the databases BioSys; Cochrane Infectious Diseases Group Specialised Register and Cochrane Central Register of Controlled Trials; EMBASE; Google Scholar; LILACS; MEDLINE (PubMed); Web of Science; and WHOLIS with the term 'ZIKA'. Systematic reviews and reviews specifying the search methods and describing potential modes of transmission were eligible for analysis.

RESULTS

Of 5,401 hits for 'Zika', 44 studies were assessed and 11 included after applying in- and exclusion criteria: six systematic reviews and five reviews with specified methods, covering all ways of possible transmission. Results can be grouped into transmission routes with good evidence and agreement between the studies (evidence on vector, mother-to-child and sexual transmission) and transmission routes with limited evidence. Transmission by breastfeeding, intrapartum, by animal bites or laboratory-based remains inconclusive, as these routes are suggested by single studies only. The risk of transfusion transmission is described and public health measures for safe transfusion should be taken as available.

CONCLUSION

Our results imply the need for public health measures to limit transmission via vectors, mother-to-child, sexual transmission and blood transfusion. Also needed are long-term prospective cohort studies covering periods of active Zika virus transmission and measuring epidemiological parameters to establish evidence on other routes of transmission; seroprevalence studies; transmission dynamics modelling and modelling health impacts by different modes of transmission.

Breastfeeding in the time of Zika: a systematic literature review

Background

The disease Zika is considered as emergent. The infection can be acquired through different routes: a bite from the Aedes mosquito, sexual contact, from mother to child during pregnancy and by blood transfusion. The possibility of Zika transmission through human lactation has been considered. Zika is a disease of great concern for public health because it has been associated with neonatal and postnatal microcephaly, among other birth defects.

Objectives

To review published evidence of the probable transmission of Zika through human lactation.

Data sources

Electronic databases: Cochrane Central Register of Controlled Trials, EBSCO, Gale, Science Direct, Scopus, US National Library of Medicine (PubMed) and Web of Science. World Health Organization and Centers for Disease Control and Prevention web pages.

Study eligibility criteria

To be eligible, studies of any design had to provide primary data of human breast milk as a potential fluid for the transmission of Zika, or primary or secondary follow-up data of infants with at least one previous published study that complied with the first criterion of eligibility.

Participants

Studies about women with suspected, probable or confirmed Zika during pregnancy, or the postnatal period and beyond. Studies about infants who breastfeed directly from the breast or where fed with the expressed breast milk of the suspected, probable or confirmed women with Zika.

Results

This study only chose data from research papers; no patients were taken directly by the authors. A total of 1,146 were screened and nine studies were included in the qualitative synthesis, from which a total of 10 cases were identified, with documented follow-up in three of these cases. Through the timing of maternal Zika infection, five cases were classified as prenatal (time before delivery), one as immediate postnatal (period from 0 to 4 days after birth); no cases were classified as medium postnatal (period from 5 days to 8 weeks after birth); two were classified as long postnatal (period from 8 weeks to 6 months after birth) and two as beyond six months after birth.

Conclusion

Human milk may be considered as a potentially infectious fluid, but we found no currently documented studies of the long-term complications in infants up to 32 months of age, with suspected, probable or confirmed Zika through human lactation, or evidence with respect to the human pathophysiology of the infection acquired through human lactation. In the light of the studies reviewed here, the World Health Organization recommendation of June 29th 2016, remains valid: “the benefits of breastfeeding for the infant and mother outweigh any potential risk of Zika virus transmission through breast milk.”

Human T cell leukemia virus type 1 and Zika virus: tale of two reemerging viruses with neuropathological sequelae of public health concern

Human T cell leukemia virus type 1 (HTLV-1) and Zika virus (ZIKV) have been considered neglected viruses of low public health concern until recently when incidences of HTLV-1 and ZIKV were observed to be linked to serious immune-related disease and neurological complications. This review will discuss the epidemiology, genomic evolution, virus-host interactions, virulence factors, neuropathological sequelae, and current perspectives of these reemerging viruses. There are no FDA-approved therapeutics or vaccines against these viruses, and as such, it is important for clinical trials to focus on developing vaccines that can induce cell-mediated immune response to confer long-term protective immunity. Furthermore, attention should be paid to reducing the transmission of these viruses through unprotected sex, infected blood during sharing of contaminated needles, donated blood and organs, and vertical transmission from mother to baby via breastfeeding. There is an urgent need to re-evaluate repurposing current antiviral therapies as well as developing novel antiviral agents with enhanced efficacy due to the high morbidity rate associated with these two reemerging chronic viral diseases.

The hidden burden of Chikungunya in central Mexico: results of a small-scale serosurvey

OBJECTIVE

To estimate the seroprevalence of CHKV antibodies and assess correlates of seropositivity at a small geographical scale.

MATERIALS AND METHODS

A community-based serosurvey of 387 households in Puente de Ixtla, Morelos (central Mexico). Serum IgG antibodies to CHKV were detected by immunoassay.

RESULTS

From 27 April to 29 May 2016, we interviewed and collected blood samples from 387 individuals at the same number of households. A total of 114 (29.5%) participants were seropositive to CHK, 36 (31.6%) of them reported no symptoms of CHKV infection within 12 months before the survey.

CONCLUSIONS

The estimated seroprevalence to CHKV antibodies was higher than expected by the small number of confirmed cases of CHKV infection reported in Mexico by the National Surveillance System.

[Ocular manifestations of emerging arboviruses: Dengue fever, Chikungunya, Zika virus, West Nile virus, and yellow fever (French translation of the article)]

Arboviruses are viral diseases transmitted by mosquitoes and tics bites. They are a major cause of morbidity and sometimes mortality. Their expansion is constant and due in part to climate change and globalization. Mostly found in tropical regions, arboviruses are sometimes the source of epidemics in Europe. Recently, the Chikungunya virus and the Zika virus were responsible for very large epidemics impacting populations that had never been in contact with those viruses. There are currently no effective antiviral treatments or vaccines. Ocular manifestations due to those infections are thus more frequent and increasingly better described. They are sometimes, as with Zika, complicated by a congenital ocular syndrome. The goal of this review is to describe the ophthalmological manifestations of Dengue fever, Chikungunya virus, Zika virus, West Nile virus, and yellow fever.

Zika virus: epidemiology, clinical aspects, diagnosis, and control of infection

Zika virus (ZIKV) is an emerging pathogen of huge public health significance to human beings. Although majority of infections are benign with self-limiting symptoms, the recent outbreak has established an association with the increased incidence of some congenital anomalies such as microcephaly. In other words, due to the large extent of the virus and mosquito vectors, the infection has become a thoughtful health problem for human societies, though now, there are no antiviral therapies or vaccines against this virus. In spite of extensive research carried out by scientists, not so much information has been gathered about this viral infection. In the current review, we prepared an overview of the remarkable progress made in understanding about the epidemiology, immunology, clinical presentation, and diagnosis methods of ZIKV infection.

Potential for the Invasive Species Aedes Albopictus and Arboviral Transmission through the Chabahar Port in Iran

BACKGROUND

Dengue, chikungunya, and Zika viruses are emerging infectious disease threats wherever suitable vectors, hosts, and habitat are present. The aim of the present study was to use the bioagent transport and environmental modeling system (BioTEMS) to identify the potential for arbovirus-infected Aedes species to invade the Chabahar area in southeastern Iran.

METHODS

ArcGIS geospatial analysis software, Statistica software, and BioTEMS were used to analyze geographic information and conduct data analysis. BioTEMS utilizes up to several hundred abiotic and biotic factors to produce risk and vulnerability assessments for biological agents and infectious diseases. The output of BioTEMS was validated using published predictive models, and most importantly published collection data of Aedes species in Iran.

RESULTS

There appears to have been two separate invasion events by Ae. albopictus into the southern region of Iran, first preceding 2009 and then again in 2013. BioTEMS identified two probable areas of introduction during the 2009 time frame, either through one or both the Chabahar ports or the Iranshahr airport with subsequent spread through vehicular transport. BioTEMS identified the port as an introduction zone for ZIKAV with high-risk zones and identifies gap zones during the 2013 time frame. Recommended surveillance sites are provided.

CONCLUSION

The air and maritime ports of Iran serve international customers, and are therefore vulnerable to import and invasion of mosquito vectors and arboviruses. Based on comparisons with other published low-resolution models, BioTEMS provides information for medical and public health professionals conducting integrated mosquito management, preventive medicine, and epidemiological surveillance.

Ocular manifestations of emerging arboviruses: Dengue fever, Chikungunya, Zika virus, West Nile virus, and yellow fever

Arboviruses are viral diseases transmitted by mosquitoes and tick bites. They are a major cause of morbidity and sometimes mortality. Their expansion is constant and due in part to climate change and globalization. Mostly found in tropical regions, arboviruses are sometimes the source of epidemics in Europe. Recently, the Chikungunya virus and the Zika virus were responsible for very large epidemics impacting populations that had never been in contact with those viruses. There are currently no effective antiviral treatments or vaccines. Ocular manifestations due to those infections are thus more frequent and increasingly better described. They are sometimes, as with Zika, complicated by a congenital ocular syndrome. The goal of this review is to describe the ophthalmological manifestations of Dengue fever, Chikungunya virus, Zika virus, West Nile virus, and yellow fever.

In Silico Designed Axl Receptor Blocking Drug Candidates Against Zika Virus Infection

After a large outbreak in Brazil, novel drugs against Zika virus became extremely necessary. Evaluation of virus-based pharmacological strategies concerning essential host factors brought us to the idea that targeting the Axl receptor by blocking its dimerization function could be critical for virus entry. Starting from experimentally validated compounds, such as RU-301, RU-302, warfarin, and R428, we identified a novel compound 2' (R428 derivative) to be the most potent for this task amongst a number of alternative compounds and leads. The improved affinity of compound 2' was confirmed by molecular docking as well as molecular dynamics simulation techniques using implicit solvation models. The current study summarizes a new possibility for inhibition of the Axl function as a potential target for future antiviral therapies.

A Review of the Ongoing Research on Zika Virus Treatment

The Zika fever is an arboviral disease resulting from the infection with Zika virus (ZIKV). The virus is transmitted to humans by the bite of Aedes mosquitos, mainly Aedes aegypti and Aedes albopictus. ZIKV has been detected for decades in African and Asian regions and, since 2007, has spread to other continents; among them, infections are most reported in the Americas. This can be explained by the presence of vectors in highly populated and tropical regions where people are susceptible to contamination. ZIKV has been considered by the World Health Organization a serious public health problem because of the increasing number of cases of congenital malformation and neurological disorders related to its infection, such as microcephaly, Guillain⁻Barré syndrome, meningoencephalitis, and myelitis. There is no vaccine or specific antiviral against ZIKV. The infection is best prevented by avoiding mosquito bite, and the treatment of infected patients is palliative. In this context, the search for efficient antivirals is necessary but remains challenging. Here, we aim to review the molecules that have been described to interfere with ZIKV life cycle and discuss their potential use in ZIKV therapy.

Neuroimaging findings associated with congenital Zika virus syndrome: case series at the time of first epidemic outbreak in Pernambuco State, Brazil

PURPOSE

This study aimed to describe the prenatal and postnatal neuroimaging and clinical findings in a clinical series following congenital Zika virus syndrome during the first epidemic Zika virus (ZIKV) outbreak in the State of Pernambuco, Brazil.

METHODS

We (the authors) conducted a retrospective study of a prospectively collected case series of fetuses and neonates with microcephaly born to mothers with presumed/confirmed congenital ZIKV syndrome. Prenatal ultrasound findings were reviewed to identify potential central nervous system (CNS) abnormalities. Neonates underwent postnatal neuroimaging follow up by computed tomography (CT)-scan or magnetic resonance (MR) imaging.

RESULTS

The prenatal and postnatal outcomes of eight fetuses/neonates born to mothers with presumed/confirmed congenital ZIKV syndrome were examined. The mean gestational age at ultrasound was 31.3 weeks. Severe microcephaly was identified in seven fetuses (87.5%), while ventriculomegaly and brain calcifications were detected in all fetuses. The mean gestational age at delivery and head circumference were 38 weeks and 30.2 cm, respectively. All cases of microcephaly but one was confirmed postnatally. Brain CT scans or MRIs were performed in seven newborns, and all had periventricular and/or parenchymal calcifications, symmetrical or asymmetrical ventriculomegaly, pachygyria, and reduced sulcation and gyration. MR imaging aided the detection of one undetected case of corpus callosum dysgenesis and was essential in documenting reduced mantel of the cerebral cortex and reduced gyration and sulcation, especially involving the parietal lobe. In addition, MR imaging was also able to display irregular interfaces with the subcortical white matter, a finding consistent with polymicrogyria, more frequently seen at the level of the frontal lobe and atrophic and thinned pons.

CONCLUSION

Severe microcephaly and CNS abnormalities may be associated with congenital ZIKV syndrome.

Zika virus: Report from the task force on tropical diseases by the world Federation of Societies of intensive and critical care medicine

Zika fever is an acute infectious disease caused by the Zika virus (ZIKV), an RNA virus belonging to the genus Flavivirus. ZIKV can be transmitted by bites from Aedes aegypti and Aedes albopictus species, sexual activity, blood transfusion and from mother to fetus during pregnancy and delivery. A total of 50 territories and countries in the Americas had reported ZIKV infections. For those with symptoms, the presentation is similar to dengue fever with body aches, joint pain, fatigue, malaise, fever and conjunctivitis lasting up to seven days. A maculopapular rash may also occur and is usually pruritic. Neurological complications are well documented and include Guillain-Barré Syndrome (GBS) and congenital ZIKV syndrome, and less frequently acute myelitis and meningoencephalitis. ZIKV infection usually causes a mild illness and most patients are managed conservatively. Currently, no antiviral therapy is available. The most appropriate therapy for ZIKV-associated GBS is yet unclear, however intravenous immunoglobulins have been used, as in conventional GBS. ZIKV infection can be prevented through the use of mosquito repellents, protection with long-sleeved clothing and trousers, and the use of clothes impregnated with permethrin. This review describes the current concepts regarding the epidemiology, diagnosis, clinical manifestations and neurological complications of ZIKV infection.

Tick-Borne Encephalitis Virus Vaccine-Induced Human Antibodies Mediate Negligible Enhancement of Zika Virus Infection InVitro and in a Mouse Model

Recent reports in the scientific literature have suggested that anti-dengue virus (DENV) and anti-West Nile virus (WNV) immunity exacerbates Zika virus (ZIKV) pathogenesis in vitro and in vivo in mouse models. Large populations of immune individuals exist for a related flavivirus (tick-borne encephalitis virus [TBEV]), due to large-scale vaccination campaigns and endemic circulation throughout most of northern Europe and the southern Russian Federation. As a result, the question of whether anti-TBEV immunity can affect Zika virus pathogenesis is a pertinent one. For this study, we obtained 50 serum samples from individuals vaccinated with the TBEV vaccine FSME-IMMUN (Central European/Neudörfl strain) and evaluated their enhancement capacity in vitro using K562 human myeloid cells expressing CD32 and in vivo using a mouse model of ZIKV pathogenesis. Among the 50 TBEV vaccinee samples evaluated, 29 had detectable reactivity against ZIKV envelope (E) protein by enzyme-linked immunosorbent assay (ELISA), and 36 showed enhancement of ZIKV infection in vitro. A pool of the most highly reacting and enhanced samples resulted in no significant change in the morbidity/mortality of ZIKV disease in immunocompromised Stat2^-/- mice. Our results suggest that humoral immunity against TBEV is unlikely to enhance Zika virus pathogenesis in humans. No clinical reports indicating that TBEV vaccinees experiencing enhanced ZIKV disease have been published so far, and though the epidemiological data are sparse, our findings suggest that there is little reason for concern. This study also displays a clear relationship between the phylogenetic distance between two flaviviruses and their capacity for pathogenic enhancement. IMPORTANCE The relationship between serial infections of two different serotypes of dengue virus and more severe disease courses is well-documented in the literature, driven by so-called antibody-dependent enhancement (ADE). Recently, studies have shown the possibility of ADE in cells exposed to anti-DENV human plasma and then infected with ZIKV and also in mouse models of ZIKV pathogenesis after passive transfer of anti-DENV human plasma. In this study, we evaluated the extent to which this phenomenon occurs using sera from individuals immunized against tick-borne encephalitis virus (TBEV). This is highly relevant, since large proportions of the European population are vaccinated against TBEV or otherwise seropositive.

Zika clinical updates: implications for pediatrics

PURPOSE OF REVIEW

Zika virus (ZIKV), a mosquito-borne flavivirus, has gained recognition over the past few years as an important new cause of congenital infection. As a result, it is critical that pediatricians understand its epidemiology, clinical presentation, clinical sequelae, and management.

RECENT FINDINGS

The recent ZIKV epidemiology, clinical presentation of acute infection in children and complications, perinatal infection, and congenital infection will be summarized in this ZIKV review. This will be followed by a brief summary on ZIKV diagnosis, management, treatment, and prevention.

SUMMARY

The field of clinical research in ZIKV has rapidly evolved over recent months. It is critical that pediatricians continue to stay up-to-date with the continuously evolving understanding of the clinical aspects of ZIKV to ensure optimal identification and management of affected infants and children. Given the recent changes in Centers for Disease Control and Prevention guidelines to limit screening of asymptomatic pregnant women in the United States with possible ZIKV exposure, comprehensive ZIKV clinical knowledge becomes even more crucial.

Zika and Public Health: Understanding the Epidemiology and Information Environment

Because Zika is a newly emerging infectious disease with little previous information known about it, there are many epidemiologic and clinical questions. The complexity of providing care to those who are at risk for infection or are already infected with Zika in this evidence-scarce environment cannot be understated. In this article, we provide an overview of the Zika virus (ZIKV) in the context of public health and pediatric health care. A broad public health focus is used to provide relevant information for addressing important questions about the epidemic and to facilitate communication with patients, parents, and caregivers within the current information environment. We explore issues regarding the epidemiology of the virus (including why ZIKV outbreaks are occurring), what has changed since the sporadic case reports before the outbreaks, why the true incidence is difficult to estimate, why attack rates vary by population and geography, and why the association between Zika and congenital Zika syndrome and Guillain-Barré syndrome have only come to light recently. Additionally, challenges related to the current information environment, traditional and informal information sources about the ZIKV, and examples of Zika public health communication campaigns are discussed. Importantly, we review the existing findings regarding the US population's Zika-related knowledge, attitudes, beliefs, and behavior by highlighting variations and gaps. We conclude by identifying related research questions that remain critical.

Zika virus infection in children: epidemiology and clinical manifestations

PURPOSE

The purpose of this review is to comprehensively review Congenital Zika Syndrome in regard to their epidemiology and clinical manifestations.

METHODS

This subject review of congenital Zika syndrome was composed after conducting a thorough review of the available literature on this topic using PubMed and other primary sources.

RESULTS

The first epidemic of Zika virus infection in Brazil was followed by an unexpected sharp increase in the incidence of infants born with microcephaly and the description of a new disease, the congenital Zika syndrome. This review focuses on the epidemiological and clinical aspects of Zika infection in children. We conducted a brief historical account of the virus description in 1947, the rare cases of Zika infection occurring up to 2007, and the first epidemics in the Pacific between 2007 and 2014. We also discussed the isolation of the virus in Brazil in 2015 and its spread in the Americas, the microcephaly outbreak in Brazil and its association with Zika virus, and the current epidemiological panorama. We address the known clinical spectrum of Zika virus infection in the pediatric population, including manifestations of acute infection and congenital Zika syndrome, with emphasis on cranial, ophthalmic, and orthopedic abnormalities.

CONCLUSION

While much has been learned about congenital Zika syndrome, the full spectrum of this infection is not yet known. This review is based on current, limited data about Zika vírus infection. As more information becomes available, we will have a more accurate picture of this new disease.