Zika virus infection: epidemiology, clinical manifestations and diagnosis

Detection and persistence of Zika virus in body fluids and associated factors: a prospective cohort study

This study aimed to analyze the detection and duration of the Zika virus (ZIKV) in plasma, urine, saliva, sweat, rectal swabs, vaginal secretions, breast milk, and semen and to explore risk factors associated with prolonged viral persistence. A prospective cohort study of symptomatic patients and their household contacts was conducted in Brazil from July 2017 to June 2019. A total of 260 individuals (184 women and 76 men) with confirmed ZIKV infection were enrolled and followed up for 12 months. ZIKV RNA was present in all body fluid specimens and detectable for extended periods in urine, sweat, rectal swabs, and semen. The longest detection duration was found in semen, with high viral loads in the specimens. ZIKV RNA clearance was associated with several factors, including age, sex, education level, body mass index, non-purulent conjunctivitis, joint pain, and whether the participant had a history of yellow fever vaccination. The influence of each of these factors on the low or fast viral clearance varied according to the specific body fluid under investigation. Recurrent ZIKV detection events after total viral clearance were observed in the cohort. Our findings provide valuable insights into the persistence and potential recurrence of ZIKV infection, highlighting the need for continued monitoring and follow-up of individuals infected with ZIKV and for effective prevention measures to reduce the risk of transmission.

Linear epitope mapping in the E and NS1 proteins of dengue and Zika viruses: Prospection of peptides for vaccines and diagnostics

The arrival of the Zika virus (ZIKV) in dengue virus (DENV)-endemic areas has posed challenges for both differential diagnosis and vaccine development. Peptides have shown promise in addressing these issues. The aim of this study was to identify the linear epitope profile recognized by serum samples from dengue and Zika patients in the E and NS1 proteins of DENV and ZIKV. This cross-sectional study included individuals of all ages with laboratory-confirmed DENV and ZIKV infections, who were selected through convenience sampling. The serum samples from dengue and Zika patients detected epitopes evenly distributed across the viral proteins in a peptide microarray platform. However, several epitopes were located within "epitope hotspots", characterized by clusters of peptides recognized in more than 30% of the sub-arrays analyzed using individual or pooled serum samples. The serum samples from dengue and Zika patients showed a high level of cross-reactivity with peptides in the DENV and ZIKV proteins. Analysis using an additional peptide microarray platform, which contained peptides selected based on the results of the initial screening, revealed that two DENV and one ZIKV peptide, highly specific to their related viruses, were located within the epitope hotspots; however, they presented low detection rates (32.5, 35.0, and 28.6%, respectively). In addition, two DENV peptides detected at similarly high rates by both dengue and Zika patients were also found within the epitope hotspots. These hotspots contain several immunodominant epitopes that are recognized by a larger number of individuals when compared to 15-amino acid (aa) sequence peptides. Thus, epitope hotspots may have greater potential to serve as antigens in diagnostic tests and vaccine development than peptides composed of only 15 amino acids.

Association of congenital Zika syndrome with dental alterations in children with microcephaly

The effects of congenital Zika syndrome (CZS) on the tooth development of infected children are not well known. The aim of this study was to analyze the association of CZS with dental alterations in children with microcephaly seen at a referral hospital in Rio Grande do Norte, Brazil. The chronology and sequence of tooth eruption and the presence of dental alterations were evaluated by a single calibrated examiner (kappa > 0.80) in 62 children aged 7 to 35 months with microcephaly associated with CZS and other congenital infections. Medical data of the mother and child were collected from the records and the parents responded to a socioeconomic questionnaire. Descriptive analysis and Fisher's exact test were used (5% significance level). The mean age of the children was 26.4 months (SD = 7.52). The mean weight and head circumference at birth were 2,593 g (SD = 0.60) and 29.6 cm (SD = 2.48), respectively. Microcephaly was associated with congenital Zika virus infection in 79% of cases and with other congenital infections in 21%. No significant association was found between CZS and alterations in the chronology (p = 1.00) or sequence of tooth eruption (p = 0.16) or changes in enamel development (p = 1.00). In conclusion, children with microcephaly exhibit a delay and alterations in the sequence of tooth eruption of primary teeth, as well as developmental defects of enamel, which are not associated with Zika virus infection.

Involvement of host microRNAs in flavivirus-induced neuropathology: An update

Flaviviruses are a spectrum of vector-borne RNA viruses that cause potentially severe diseases in humans including encephalitis, acute-flaccid paralysis, cognitive disorders and foetal abnormalities. Japanese encephalitis virus (JEV), Zika virus (ZIKV), West Nile virus (WNV) and Dengue virus (DENV) are globally emerging pathogens that lead to epidemics and outbreaks with continued transmission to newer geographical areas over time. In the past decade, studies have focussed on understanding the pathogenic mechanisms of these viruses in a bid to alleviate their disease burden. MicroRNAs (miRNAs) are short single-stranded RNAs that have emerged as master-regulators of cellular gene expression. The dynamics of miRNAs within a cell have the capacity to modulate hundreds of genes and, consequently, their physiological manifestation. Increasing evidence suggests their role in host response to disease and infection including cell survival, intracellular viral replication and immune activation. In this review, we aim to comprehensively update published evidence on the role of miRNAs in host cells infected with the common neurotropic flaviviruses, with an increased focus on neuropathogenic mechanisms. In addition, we briefly cover therapeutic advancements made in the context of miRNA-based antiviral strategies.

Zika a Vector Borne Disease Detected in Newer States of India Amidst the COVID-19 Pandemic

Background

During the second wave of the COVID-19 pandemic, outbreaks of Zika were reported from Kerala, Uttar Pradesh, and Maharashtra, India in 2021. The Dengue and Chikungunya negative samples were retrospectively screened to determine the presence of the Zika virus from different geographical regions of India.

Methods

During May to October 2021, the clinical samples of 1475 patients, across 13 states and a union territory of India were screened and re-tested for Dengue, Chikungunya and Zika by CDC Trioplex Real time RT-PCR. The Zika rRTPCR positive samples were further screened with anti-Zika IgM and Plaque Reduction Neutralization Test. Next generation sequencing was used for further molecular characterization.

Results

The positivity was observed for Zika (67), Dengue (121), and Chikungunya (10) amongst screened cases. The co-infections of Dengue/Chikungunya, Dengue/Zika, and Dengue/Chikungunya/Zika were also observed. All Zika cases were symptomatic with fever (84%) and rash (78%) as major presenting symptoms. Of them, four patients had respiratory distress, one presented with seizures, and one with suspected microcephaly at birth. The Asian Lineage of Zika and all four serotypes of Dengue were found in circulation.

Conclusion

Our study indicates the spread of the Zika virus to several states of India and an urgent need to strengthen its surveillance.

The roles of epidermal growth factor receptor in viral infections

Viruses are intracellular pathogen that exploit host cellular machinery for their propagation. Extensive research on virus-host interaction have shed light on an alternative antiviral strategy that targets host cell factors. Epidermal growth factor receptor (EGFR) is a versatile signal transducer that is involved in a range of cellular processes. Numerous studies have revealed how viruses exploit the function of EGFR in different stages of viral life cycle. In general, viruses attach onto the host cell surface and interacts with EGFR to facilitate viral entry, viral replication and spread as well as evasion from host immunosurveillance. Moreover, virus-induced activation of EGFR signalling is associated with mucin expression, tissue damage and carcinogenesis that contribute to serious complications. Herein, we review our current understanding of roles of EGFR in viral infection and its potential as therapeutic target in managing viral infection. We also discuss the available EGFR-targeted therapies and their limitations.

Neurogenesis and Viral Infection

Neural stem cells (NSCs) are multipotent stem cells that reside in the fetal and adult mammalian brain, which can self-renew and differentiate into neurons and supporting cells. Intrinsic and extrinsic cues, from cells in the local niche and from distant sites, stringently orchestrates the self-renewal and differentiation competence of NSCs. Ample evidence supports the important role of NSCs in neuroplasticity, aging, disease, and repair of the nervous system. Indeed, activation of NSCs or their transplantation into injured areas of the central nervous system can lead to regeneration in animal models. Viral invasion of NSCs can negatively affect neurogenesis and synaptogenesis, with consequent cell death, impairment of cell cycle progression, early differentiation, which cause neural progenitors depletion in the cortical layer of the brain. Herein, we will review the current understanding of Zika virus (ZIKV) infection of the fetal brain and the NSCs, which are the preferential population targeted by ZIKV. Furthermore, the potential neurotropic properties of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which may cause direct neurological damage, will be discussed.

Identification of a small compound that specifically inhibits Zika virus in vitro and in vivo by targeting the NS2B-NS3 protease

Zika virus (ZIKV) has rapid become a global threat, but no ZIKV-specific vaccines or drugs are currently available. In this study, inhibitors of ZIKV NS2B-NS3 protease were screened from a library containing 4,452 compound fragments. One of the compounds, 6-bromo-1,2-naphthalenedione, exhibited high specific inhibition against ZIKV NS2B-NS3 protease, but had no inhibitory effects against other viral proteases. A microscale thermophoresis (MST) assay confirmed that the compound bound to ZIKV NS2B-NS3 protein with a binding constant (Kd) of 12.26 μM. Indirect immunofluorescence assays, Western blots, and plaque assays indicated that the compound inhibited virus replication in cells. Virus titer was reduced by more than 75% when the compound was present at 1 μM. A time-of-addition assay showed that inhibition occurred at the virus replication stage, but not at the adsorption or invasion stages. The half cytotoxicity concentration (CC50) of the compound on HeLa, Vero, and BHK-21 cells were 445.44 μM, 123.87 μM, and 123.64 μM, respectively. In vivo tests using infected AG129 mice demonstrated that treatment with the compound reduced mortality by up to 60%. Mice treated with the compound showed a reduction in histopathological lesions in brain, testis, and ovary. Viral RNA, IL-1β, and IL-6 mRNA levels decreased significantly in these tissues. In summary, this study has identified a small compound with high and specific inhibitory effects on ZIKV. The compound can be used as a therapeutic agent and is also an ideal starting point for drug optimization.

Differential detection of zika virus based on PCR

Tropical countries are highly prone to infectious diseases such as the one caused by zika virus. Infection by zika is clinically and epidemiologically highly relevant. For example, when women are infected by zika during the first trimester of pregnancy, the child incurs a high risk of microcephaly and acute neurological syndromes. In adults, the virus is associated with the Guillain-Barré syndrome and other disorders. The worldwide emergency caused by zika in 2013/14 demonstrated the need for rapid and accurate diagnostic tools for the virus. Current diagnostic methods include virus isolation, serological tests, and molecular assays. However, virus isolation requires labor-intensive and time-consuming cell culture; serological detection suffers from cross-reactivity caused by previous exposure to homologous arboviruses that cause symptoms like those caused by zika, while molecular tools commonly are not designed for differential zika detection. This work reports on developing a specific molecular detection method based on phylogenetically conserved primers designed for the specific diagnosis of the zika virus. The zika primers were systematically selected through a rigorous bioinformatic analysis and demonstrated the capability to be highly specific. We tested our primers on synthetic DNA, cell cultures and samples from patients infected with zika, dengue and chikungunya and found that they detected zika with specificity high enough for differential virus diagnosis.

Alkyne-Tagged Apigenin, a Chemical Tool to Navigate Potential Targets of Flavonoid Anti-Dengue Leads

A flavonoid is a versatile core structure with various cellular, immunological, and pharmacological effects. Recently, flavones have shown anti-dengue activities by interfering with viral translation and replication. However, the molecular target is still elusive. Here we chemically modified apigenin by adding an alkyne moiety into the B-ring hydroxyl group. The alkyne serves as a chemical tag for the alkyne-azide cycloaddition reaction for subcellular visualization. The compound located at the perinuclear region at 1 and 6 h after infection. Interestingly, the compound signal started shifting to vesicle-like structures at 6 h and accumulated at 24 and 48 h after infection. Moreover, the compound treatment in dengue-infected cells showed that the compound restricted the viral protein inside the vesicles, especially at 48 h. As a result, the dengue envelope proteins spread throughout the cells. The alkyne-tagged apigenin showed a more potent efficacy at the EC₅₀ of 2.36 ± 0.22, and 10.55 ± 3.37 µM, respectively, while the cytotoxicities were similar to the original apigenin at the CC₅₀ of 70.34 ± 11.79, and 82.82 ± 11.68 µM, respectively. Molecular docking confirmed the apigenin binding to the previously reported target, ribosomal protein S9, at two binding sites. The network analysis, homopharma, and molecular docking revealed that the estrogen receptor 1 and viral NS1 were potential targets at the late infection stage. The interactions could attenuate dengue productivity by interfering with viral translation and suppressing the viral proteins from trafficking to the cell surface.

Flavonoids as Molecules With Anti-Zika virus Activity

Zika virus (ZIKV) is an arthropod-born virus that is mainly transmitted to humans by mosquitoes of the genus Aedes spp. Since its first isolation in 1947, only a few human cases had been described until large outbreaks occurred on Yap Island (2007), French Polynesia (2013), and Brazil (2015). Most ZIKV-infected individuals are asymptomatic or present with a self-limiting disease and nonspecific symptoms such as fever, myalgia, and headache. However, in French Polynesia and Brazil, ZIKV outbreaks led to the diagnosis of congenital malformations and microcephaly in newborns and Guillain-Barré syndrome (GBS) in adults. These new clinical presentations raised concern from public health authorities and highlighted the need for anti-Zika treatments and vaccines to control the neurological damage caused by the virus. Despite many efforts in the search for an effective treatment, neither vaccines nor antiviral drugs have become available to control ZIKV infection and/or replication. Flavonoids, a class of natural compounds that are well-known for possessing several biological properties, have shown activity against different viruses. Additionally, the use of flavonoids in some countries as food supplements indicates that these molecules are nontoxic to humans. Thus, here, we summarize knowledge on the use of flavonoids as a source of anti-ZIKV molecules and discuss the gaps and challenges in this area before these compounds can be considered for further preclinical and clinical trials.

SARS-CoV-2 in Pregnancy: Fitting Into the Existing Viral Repertoire

The risk of viral infection during pregnancy is well-documented; however, the intervention modalities that in practice enable maternal-fetal protection are restricted by limited understanding. This becomes all the more challenging during pandemics. During many different epidemic and pandemic viral outbreaks, worse outcomes (fetal abnormalities, mortality, preterm labor, etc.) seem to affect pregnant women than what has been evident when compared to non-pregnant women. The condition of pregnancy, which is widely understood as "immunosuppressed," needs to be re-understood in terms of the way the immune system works during such a state. The immune system gets transformed to accommodate and facilitate fetal growth. The interference of such supportive conversion by viral infection and the risk of co-infection lead to adverse fetal outcomes. Hence, it is crucial to understand the risk and impact of potent viral infections likely to be encountered during pregnancy. In the present article, we review the effects imposed by previously established and recently emerging/re-emerging viral infections on maternal and fetal health. Such understanding is important in devising strategies for better preparedness and knowing the treatment options available to mitigate the relevant adverse outcomes.

Hepatic Manifestations of Nonhepatotropic Infectious Agents Including Severe Acute Respiratory Syndrome Coronavirus-2, Adenovirus, Herpes Simplex Virus, and Coxiella burnetii

Nonhepatotropic viruses such as adenovirus, herpes simplex virus, flaviviruses, filoviruses, and human herpes virus, and bacteria such as Coxiella burnetii, can cause liver injury mimicking acute hepatitis. Most of these organisms cause a self-limited infection. However, in immunocompromised patients, they can cause severe hepatitis or in some cases fulminant hepatic failure requiring an urgent liver transplant. Hepatic dysfunction is also commonly seen in patients with severe acute respiratory syndrome coronavirus-2 infection. Patients with preexisting liver diseases are likely at risk for severe coronavirus disease 2019 (COVID-19) and may be associated with poor outcomes.

Untargeted Metabolomics Insights into Newborns with Congenital Zika Infection

Zika virus (ZIKV), an emerging virus belonging to the Flaviviridae family, causes severe neurological clinical complications and has been associated with Guillain-Barré syndrome, fetal abnormalities known collectively as congenital Zika syndrome, and microcephaly. Studies have shown that ZIKV infection can alter cellular metabolism, directly affecting neural development. Brain growth requires controlled cellular metabolism, which is essential for cell proliferation and maturation. However, little is known regarding the metabolic profile of ZIKV-infected newborns and possible associations related to microcephaly. Furthering the understanding surrounding underlying mechanisms is essential to developing personalized treatments for affected individuals. Thus, metabolomics, the study of the metabolites produced by or modified in an organism, constitutes a valuable approach in the study of complex diseases. Here, 26 serum samples from ZIKV-positive newborns with or without microcephaly, as well as controls, were analyzed using an untargeted metabolomics approach involving gas chromatography-mass spectrometry (GC-MS). Significant alterations in essential and non-essential amino acids, as well as carbohydrates (including aldohexoses, such as glucose or mannose) and their derivatives (urea and pyruvic acid), were observed in the metabolic profiles analyzed. Our results provide insight into relevant metabolic processes in patients with ZIKV and microcephaly.

DNA Nanostructures in the Fight Against Infectious Diseases

Throughout history, humanity has been threatened by countless epidemic and pandemic outbreaks of infectious diseases, from the Justinianic Plague to the Spanish flu to COVID-19. While numerous antimicrobial and antiviral drugs have been developed over the last 200 years to face these threats, the globalized and highly connected world of the 21st century demands for an ever-increasing efficiency in the detection and treatment of infectious diseases. Consequently, the rapidly evolving field of nanomedicine has taken up the challenge and developed a plethora of strategies to fight infectious diseases with the help of various nanomaterials such as noble metal nanoparticles, liposomes, nanogels, and virus capsids. DNA nanotechnology represents a comparatively recent addition to the nanomedicine arsenal, which, over the past decade, has made great progress in the area of cancer diagnostics and therapy. However, the past few years have seen also an increasing number of DNA nanotechnology-related studies that particularly focus on the detection and inhibition of microbial and viral pathogens. Herein, a brief overview of this rather young research field is provided, successful concepts as well as potential challenges are identified, and promising directions for future research are highlighted.

Neurologic Manifestations of the World Health Organization's List of Pandemic and Epidemic Diseases

The World Health Organization (WHO) monitors the spread of diseases globally and maintains a list of diseases with epidemic or pandemic potential. Currently listed diseases include Chikungunya, cholera, Crimean-Congo hemorrhagic fever, Ebola virus disease, Hendra virus infection, influenza, Lassa fever, Marburg virus disease, Neisseria meningitis, MERS-CoV, monkeypox, Nipah virus infection, novel coronavirus (COVID-19), plague, Rift Valley fever, SARS, smallpox, tularemia, yellow fever, and Zika virus disease. The associated pathogens are increasingly important on the global stage. The majority of these diseases have neurological manifestations. Those with less frequent neurological manifestations may also have important consequences. This is highlighted now in particular through the ongoing COVID-19 pandemic and reinforces that pathogens with the potential to spread rapidly and widely, in spite of concerted global efforts, may affect the nervous system. We searched the scientific literature, dating from 1934 to August 2020, to compile data on the cause, epidemiology, clinical presentation, neuroimaging features, and treatment of each of the diseases of epidemic or pandemic potential as viewed through a neurologist's lens. We included articles with an abstract or full text in English in this topical and scoping review. Diseases with epidemic and pandemic potential can be spread directly from human to human, animal to human, via mosquitoes or other insects, or via environmental contamination. Manifestations include central neurologic conditions (meningitis, encephalitis, intraparenchymal hemorrhage, seizures), peripheral and cranial nerve syndromes (sensory neuropathy, sensorineural hearing loss, ophthalmoplegia), post-infectious syndromes (acute inflammatory polyneuropathy), and congenital syndromes (fetal microcephaly), among others. Some diseases have not been well-characterized from a neurological standpoint, but all have at least scattered case reports of neurological features. Some of the diseases have curative treatments available while in other cases, supportive care remains the only management option. Regardless of the pathogen, prompt, and aggressive measures to control the spread of these agents are the most important factors in lowering the overall morbidity and mortality they can cause.

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.

Exploring the influence of deforestation on dengue fever incidence in the Brazilian Amazonas state

INTRODUCTION

Dengue fever is the most prevalent arboviral disease in the Brazilian Amazon and places a major health, social and economic burden on the region. Its association with deforestation is largely unknown, yet the clearing of tropical rainforests has been linked to the emergence of several infectious diseases, including yellow fever and malaria. This study aimed to explore potential drivers of dengue emergence in the Brazilian Amazon with a focus on deforestation.

METHODS

An ecological study design using municipality-level secondary data from the Amazonas state between 2007 and 2017 (reported rural dengue cases, incremental deforestation, socioeconomic characteristics, healthcare and climate factors) was employed. Data were transformed according to the year with the most considerable deforestation. Associations were explored using bivariate analysis and a multivariate generalised linear model.

RESULTS

During the study period 2007-2017, both dengue incidence and deforestation increased. Bivariate analysis revealed increased incidences for some years after deforestation (e.g. mean difference between dengue incidence before and three years after deforestation was 55.47 cases per 100,000, p = 0.002), however, there was no association between the extent of deforestation and dengue incidence. Using a negative binomial regression model adjusted for socioeconomic, climate and healthcare factors, deforestation was not found to be related to dengue incidence. Access to healthcare was found to be the only significant predictor of dengue incidence.

DISCUSSION

Previous research has shown that deforestation facilitates the emergence of vector-borne diseases. However, no significant dose-response relationships between dengue incidence and deforestation in the Brazilian Amazonas state were found in this study. The finding that access to healthcare was the only significant predictor of dengue incidence suggests that incidence may be more dependent on surveillance than transmission. Further research and public attention are needed to better understand environmental effects on human health and to preserve the world's largest rainforest.

The anti-Zika virus and anti-tumoral activity of the citrus flavanone lipophilic naringenin-based compounds

Flavonoids are natural products widely recognized for their plurality of applications such as antiviral, antiproliferative, antitumor activities and, antioxidant properties. The flavanone naringenin is presented in citrus fruits and has been studied to combat recurrent diseases that still lack effective treatment. Research groups have been investing efforts to the development of new, safe and active candidates to combat these agents or conditions and despite good results recently reported against the Zika virus (ZIKV) and tumor cells, the use of citrus naringenin is limited due to its low bioavailability. Structural exchanges through functionalization, for example, attaching lipophilic groups instead of hydroxyl groups, can further enhance biological properties. Here, the synthesis and characterization of regioselective naringenin mono-7-O-ethers and both mono and di-fatty acid esters, structurally lipophilic ones were demonstrated. Finally, in vitro studies of anti-ZIKV action and antiproliferative activities against melanoma (B16-F10) and breast carcinoma (4T1) cells showed the ether derivatives were actives, with IC₅₀ ranging from 6.76, 18.5 and 22.6 μM to 28.53, 45.1 and 32.3 μM referring to ZIKV, B16-F10 and 4T1 cell lines, respectively. The lipophilic ethers present the ability to inhibit selectively ZIKV-replication in human cells and inhibitions. This class of modifications in flavonoid molecules could be further explore in the future development of specific anti-ZIKV compounds.

The rash with mucosal ulceration

A rash is a disseminated eruption of cutaneous lesions with great variation in appearance, cause, and severity. When the physician is facing a rash, the history and physical examination of the patient are extremely important for the identification of the disease and its causal agent. There are various causes for a rash, which may be infectious, allergic, or rheumatologic, besides many others. Rashes associated with mucosal ulcers may have causes related to viral and bacterial infections or drug reactions. They may be associated with measles; erythema infectiosum; roseola infantum; rubella; hand, foot, and mouth disease; pityriasis rosea; dengue fever; chikungunya; zika; scarlet fever; meningococcal diseases; syphilis; and exanthematous drug eruptions.

Zika Virus Transmission Through Blood Tissue Barriers

The recent Zika virus (ZIKV) epidemic in the Americas and the Caribbean revealed a new deadly strain of the mosquito-borne virus, which has never been associated with previous outbreaks in Asia. For the first time, widespread ZIKV infection was shown to cause microcephaly and death of newborns, which was most likely due to the mutation acquired during the large outbreak recorded in French Polynesia in 2013–2014. Productive ZIKV replication and persistence has been demonstrated in placenta and fetal brains. Possible association between ZIKV and microcephaly and fetal death has been confirmed using immunocompetent mouse models in vitro and in vivo. Having crossed the placenta, ZIKV directly targets neural progenitor cells (NPCs) in developing human fetus and triggers apoptosis. The embryonic endothelial cells are exceptionally susceptible to ZIKV infection, which causes cell death and tissue necrosis. On the contrary, ZIKV infection does not affect the adult brain microvascular cell morphology and blood–brain barrier function. ZIKV is transmitted primarily by Aedes mosquito bite and is introduced into the placenta/blood through replication at the site of the entry. Also, virus can be transmitted through unprotected sex. Although, multiple possible routes of virus infection have been identified, the exact mechanism(s) utilized by ZIKV to cross the placenta still remain largely unknown. In this review, the current understanding of ZIKV infection and transmission through the placental and brain barriers is summarized.

Comprehensive Evaluation of Differential Serodiagnosis between Zika and Dengue Viral Infections

Diagnostic testing for Zika virus (ZIKV) or dengue virus (DENV) infection can be accomplished by a nucleic acid detection method; however, a negative result does not exclude infection due to the low virus titer during infection depending on the timing of sample collection. Therefore, a ZIKV- or DENV-specific serological assay is essential for the accurate diagnosis of patients and to mitigate potential severe health outcomes. A retrospective study design with dual approaches of collecting human serum samples for testing was developed. All serum samples were extensively evaluated by using both noninfectious wild-type (wt) virus-like particles (VLPs) and soluble nonstructural protein 1 (NS1) in the standard immunoglobulin M (IgM) antibody-capture enzyme-linked immunosorbent assay (MAC-ELISA). Both ZIKV-derived wt-VLP- and NS1-MAC-ELISAs were found to have similar sensitivities for detecting anti-premembrane/envelope and NS1 antibodies from ZIKV-infected patient sera, although lower cross-reactivity to DENV2/3-NS1 was observed. Furthermore, group cross-reactive (GR)-antibody-ablated homologous fusion peptide-mutated (FP)-VLPs consistently showed higher positive-to-negative values than homologous wt-VLPs. Therefore, we used DENV-2/3 and ZIKV FP-VLPs to develop a novel, serological algorithm for differentiating ZIKV from DENV infection. Overall, the sensitivity and specificity of the FP-VLP-MAC-ELISA and the NS1-MAC-ELISA were each higher than 80%, with no statistical significance. The accuracy can reach up to 95% with the combination of FP-VLP and NS1 assays. In comparison to current guidelines using neutralization tests to measure ZIKV antibody, this approach can facilitate laboratory screening for ZIKV infection, especially in regions where DENV infection is endemic and capacity for neutralization testing does not exist.

The Asian Lineage of Zika Virus: Transmission and Evolution in Asia and the Americas

Since first isolation in 1947 from the Zika forest in Uganda, Zika virus (ZIKV) has been principally known as a benign agent associated with sporadic human infections in a restricted number of African countries. However, during 2015-2016, an Asian lineage of ZIKV caused an unprecedentedly large outbreak in the Americas and sizeable numbers of exported cases across the globe. In this review, we critically appraise the recent advances in molecular epidemiological studies of ZIKV performed to date, and we highlight the pivotal role played by genomic surveillance in elucidating the origins, dissemination and evolution of the Asian lineage of ZIKV in Asia and in the Americas.

Zika virus differentially infects human neural progenitor cells according to their state of differentiation and dysregulates neurogenesis through the Notch pathway

Zika virus (ZIKV) is a mosquito-borne Flavivirus that causes Zika disease with particular neurological complications, including Guillain-Barré Syndrome and congenital microcephaly. Although ZIKV has been shown to directly infect human neural progenitor cells (hNPCs), thereby decreasing their viability and growth, it is as yet unknown which of the cellular pathways involved in the disruption of neurogenesis are affected following ZIKV infection. By comparing the effect of two ZIKV strains in vitro on hNPCs, the differentiation process of the latter cells was found to lead to a decreased susceptibility to infection and cell death induced by each of the ZIKV strains, which was associated with an earlier and stronger antiviral innate immune response in infected, differentiated hNPCs, as compared to undifferentiated cells. Moreover, ZIKV modulated, both in hNPCs and in vivo in fetal brain in an experimental mouse model, the expression of the Notch pathway which is involved in cellular proliferation, apoptosis and differentiation during neurogenesis. These results show that the differentiation state of hNPCs is a significant factor contributing to the outcome of ZIKV infection and furthermore suggest that ZIKV infection might initiate early activation of the Notch pathway resulting in an abnormal differentiation process, implicated in ZIKV-induced brain injury.

Advances in Diagnostic Methods for Zika Virus Infection

The Zika virus (ZIKV) is one of the most infamous mosquito-borne flavivirus on recent memory due to its potential association with high mortality rates in fetuses, microcephaly and neurological impairments in neonates, and autoimmune disorders. The severity of the disease, as well as its fast spread over several continents, has urged the World Health Organization (WHO) to declare ZIKV a global health concern. In consequence, over the past couple of years, there has been a significant effort for the development of ZIKV diagnostic methods, vaccine development, and prevention strategies. This review focuses on the most recent aspects of ZIKV research which includes the outbreaks, genome structure, multiplication and propagation of the virus, and more importantly, the development of serological and molecular detection tools such as Zika IgM antibody capture enzyme-linked immunosorbent assay (Zika MAC-ELISA), plaque reduction neutralization test (PRNT), reverse transcription quantitative real-time polymerase chain reaction (qRT-PCR), reverse transcription-loop mediated isothermal amplification (RT-LAMP), localized surface plasmon resonance (LSPR) biosensors, nucleic acid sequence-based amplification (NASBA), and recombinase polymerase amplification (RPA). Additionally, we discuss the limitations of currently available diagnostic methods, the potential of newly developed sensing technologies, and also provide insight into future areas of research.

Identification of peptide based B-cell epitopes in Zika virus NS1

Zika virus (ZIKV), a mosquito-borne flavivirus that has recently emerged globally, poses a major threat to public health. To control this emerging disease, accurate diagnostics are required for monitoring current ZIKV outbreaks. Owing to the high nucleotide sequence similarity and cross-reactivity of ZIKV with other members of the Flaviviridae family, discrimination from other flavivirus infections is often difficult in endemic areas. ZIKV NS1 induces major virus-specific antibodies and is therefore utilized as a serological marker for ZIKV diagnosis. To identify ZIKV specific epitopes for clinical application, 33 NS1 peptides that are 15-30 amino acid in length covering whole NS1 were synthesized and analyzed linear B-cell epitopes with 38 human serum samples (20 ZIKV-positive and 18 ZIKV-negative). As a result of screening, eight epitope regions were identified. In particular, the Z8 and Z14 peptides located in the β-ladder surface region showed higher levels of binding activity in ZIKV-positive sera without cross-reactivity to other flaviviruses. These identified sensitive and specific epitopes provide a tool for design of diagnostics and structure-based vaccine antigens for ZIKV infection.

Readiness for an Increase in Congenital Zika Virus Infections in the United States: Geographic Distance to Pediatric Subspecialist Care

OBJECTIVE

The study's purpose was to investigate readiness for an increase in the congenital Zika infection (CZI) by describing the distribution of pediatric subspecialists needed for the care of children with CZI.

METHODS

We applied county-level subspecialist counts to US maps, overlaying the geocoded locations of children's hospitals to assess the correlation of hospital and subspecialist locations. We calculated travel distance from census tract centroids to the nearest in-state children's hospital by state (with/without > 100 reported adult Zika virus cases) and by regions corresponding to the likely local Zika virus transmission area and to the full range of the mosquito vector. Travel distance percentiles reflect the population of children 100 miles.

CONCLUSION

The travel distance to pediatric subspecialty care varies widely by state and is likely to be an access barrier in some areas, particularly states bordering the Gulf of Mexico, which may have increasing numbers of CZI cases. (Disaster Med Public Health Preparedness. 2019;13:476-486).

Polymeric Prodrugs Targeting Polyamine Metabolism Inhibit Zika Virus Replication

The Zika virus (ZIKV) is primarily transmitted via an infected mosquito bite, during sexual intercourse, or in utero mother to child transmission. When a fetus is infected, both neurological malformations and deficits in brain development are frequently manifested. As such, there is a need for vaccines or drugs that may be used to cure ZIKV infections. Metabolic pathways play a crucial role in cell differentiation and development. More importantly, polyamines play a key role in replication and translation of several RNA viruses, including ZIKV, Dengue virus, and Chikungunya virus. Here, we present polyamine analogues (BENSpm and PG11047) and their corresponding polymer prodrug derivatives for inhibiting ZIKV infection by intersecting with polyamine catabolism pathways. We tested the compounds against ZIKV African (MR766) and Asian (PRVABC59) strains in human kidney epithelial (Vero) and glioblastoma derived (SNB-19) cell lines. Our results demonstrate potent inhibition of ZIKV viral replication in both cell lines tested. This antiviral effect was mediated by the upregulation of two polyamine catabolic enzymes, spermine oxidase, and spermidine (SMOX)/spermine N1-acetyltransferase (SAT1) as apparent reduction of the ZIKV infection following heterologous expression of SMOX and SAT1. On the basis of these observations, we infer potential use of these polyamine analogues to treat ZIKV infections.

Consequences of in utero exposure to Zika virus in offspring of AG129 mice

Zika virus (ZIKV) can cause various diseases in offspring after congenital infection. The purpose of this study was to identify disease phenotypes in pups exposed to ZIKV in utero. Female interferon-α/β, -γ receptor knockout mice (AG129) were infected intraperitoneally with ZIKV 7.5 days' post coitus (dpc). Viral RNA, antigen and infectious virus were detected in some, but not all, maternal and fetal tissues at various times during gestation. Fetuses of infected dams had significant intrauterine growth restriction (IUGR), which was more pronounced as females neared parturition. Pups born to infected dams were significantly smaller and had significantly shortened skull lengths, as determined by measurement with a caliper and by micro-CT analysis, as compared with age-matched controls. Growth rates of exposed pups after birth, however, was similar to sham-exposed offspring. Viral RNA was detected in pups of infected dams after birth. A lower survival rate was observed in neonates exposed to ZIKV in utero. A mortality rate of over 50%, attributed to consequences of ZIKV infection, occurred after birth in pups born to infected dams. A transient hearing loss was observed in some animals exposed to virus in utero. No motor deficits or cognitive deficits were detected using running wheel or viral paresis scoring assays. Abnormalities in offspring included smaller size, shorter skull length and increased neonatal mortality, while the only functional deficit we could detect was a low incidence of transient hearing loss.

Incorporation of IgG Depletion in a Neutralization Assay Facilitates Differential Diagnosis of Zika and Dengue in Secondary Flavivirus Infection Cases

Zika virus (ZIKV) has emerged as a major global public health concern due to its link as a causative agent of human birth defects. Laboratory diagnosis of suspected ZIKV infections by serological testing of specimens collected a week or more after symptom onset primarily relies on detection of anti-ZIKV-specific IgM antibodies by enzyme-linked immunosorbent assay coupled with detection of ZIKV-specific neutralizing antibody by neutralization tests. A definitive diagnosis based on serological assays is possible during primary ZIKV infections; however, due to the cross-reactivity of antibodies elicited during flaviviral infections, a definitive diagnosis is not always possible, especially among individuals who have previously been exposed to closely related flaviviruses, such as dengue virus (DENV). Here, we investigated the neutralizing IgM antibody profiles of 33 diagnostic specimens collected from individuals with suspected primary and secondary flaviviral infections acquired when visiting areas experiencing active ZIKV transmission in 2015 and 2016. Specimens collected between 1 day and 3 months postexposure were tested for ZIKV and dengue virus type 1 (DENV1) and type 2 (DENV2) by the plaque reduction neutralization test (PRNT) before and after IgG depletion. We found that IgG depletion prior to neutralization testing had little effect in differentiating samples from individuals with secondary infections taken less than 3 weeks postexposure; however, IgG depletion significantly reduced the cross-reactive neutralizing antibody titers and increased the percentage of cases discernible by PRNT from 15.4% (95% confidence interval [CI], 4.3 to 42.2%) to 76.9% (95% CI, 49.7 to 91.8%) for samples collected between roughly 3 and 12 weeks postexposure. These results highlight the potential of IgG depletion to improve the specificity of PRNT for better confirmation and differential diagnosis of flavivirus infections.

Cathelicidin-Derived Antimicrobial Peptides Inhibit Zika Virus Through Direct Inactivation and Interferon Pathway

Zika virus (ZIKV) is a neurotrophic flavivirus that is able to infect pregnant women and cause fetal brain abnormalities. Although there is a significant effort in identifying anti-ZIKV strategies, currently no vaccines or specific therapies are available to treat ZIKV infection. Antimicrobial peptides, which are potent host defense molecules in nearly all forms of life, have been found to be effective against several types of viruses such as HIV-1 and influenza A. However, they have not been tested in ZIKV infection. To determine whether antimicrobial peptides have anti-ZIKV effects, we used nine peptides mostly derived from human and bovine cathelicidins. Two peptides, GF-17 and BMAP-18, were found to have strong anti-ZIKV activities and little toxicity at 10 µM in an African green monkey kidney cell line. We further tested GF-17 and BMAP-18 in human fetal astrocytes, a known susceptible cell type for ZIKV, and found that GF-17 and BMAP-18 effectively inhibited ZIKV regardless of whether peptides were added before or after ZIKV infection. Interestingly, inhibition of type-I interferon signaling resulted in higher levels of ZIKV infection as measured by viral RNA production and partially reversed GF-17-mediated viral inhibition. More importantly, pretreatment with GF-17 and BMAP-18 did not affect viral attachment but reduced viral RNA early in the infection course. Direct incubation with GF-17 for 1 to 4 h specifically reduced the number of infectious Zika virions in the inoculum. In conclusion, these findings suggest that cathelicidin-derived antimicrobial peptides inhibit ZIKV through direct inactivation of the virus and via the interferon pathway. Strategies that harness antimicrobial peptides might be useful in halting ZIKV infection.

Effects of climate change on the spread of zika virus: a public health threat

Zika is a vector-borne viral disease transmitted to humans primarily by Aedes aegypti mosquitoes. The increased climate instability has contributed to the emergence of infections carried by mosquitoes like dengue, chikungunya and zika. While infection with the zika virus is not new, the recent epidemic of microcephaly in Brazil and other countries in South America resulting from the infection of pregnant women with the zika virus raise a number of serious public health concerns. These include the question of how climate change affects the range of zika vectors, what can we do to shorten the length of mosquito season, how and why the symptoms of zika infection have changed and what can be done to reduce the burden of human disease from this infection? Another important question that needs to be answered is what are the factors that caused the zika virus to leave the non-human primates and/or other mammals and invade the human population?

Immunization with phage virus-like particles displaying Zika virus potential B-cell epitopes neutralizes Zika virus infection of monkey kidney cells

Zika virus (ZIKV) is a mosquito-borne flavivirus that has re-emerged and is associated with many debilitating clinical manifestations. Research is currently being conducted to develop a prophylactic vaccine against the virus; however, there has not been any licensed ZIKV vaccine. Recent studies have identified potential B-cell epitopes (amino acids 241-259, 294-315, 317-327, 346-361, 377-388 and 421-437) on the envelope protein of ZIKV, which could be explored to develop peptide vaccines against ZIKV infection. Nevertheless, the immunogenicity of these epitopes has never been assessed. Here, we displayed these epitopes on highly immunogenic bacteriophage virus-like particles (VLPs; MS2, PP7 and Qβ) platforms and assessed their immunogenicity in mice. Mice immunized with a mixture of VLPs displaying ZIKV envelope B-cell epitopes elicited anti-ZIKV antibodies. Although, immunized mice were not protected against a high challenge dose of ZIKV, sera - albeit at low titers - from immunized mice neutralized (in vitro) a low dose of ZIKV. Taken together, these results show that these epitopes are B-cell epitopes and they are immunogenic when displayed on a Qβ VLP platform. Furthermore, the results also show that immunization with VLPs displaying a single B-cell epitope minimally reduces ZIKV infection whereas immunization with a mixture of VLPs displaying a combination of the B-cell epitopes neutralizes ZIKV infection. Thus, immunization with a mixture of VLPs displaying multiple ZIKV B-cell epitopes is a good strategy to enhance ZIKV neutralization.

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.

Advances in Diagnosis, Surveillance, and Monitoring of Zika Virus: An Update

Zika virus (ZIKV) is associated with numerous human health-related disorders, including fetal microcephaly, neurological signs, and autoimmune disorders such as Guillain-Barré syndrome (GBS). Perceiving the ZIKA associated losses, in 2016, the World Health Organization (WHO) declared it as a global public health emergency. In consequence, an upsurge in the research on ZIKV was seen around the globe, with significant attainments over developing several effective diagnostics, drugs, therapies, and vaccines countering this life-threatening virus at an early step. State-of-art tools developed led the researchers to explore virus at the molecular level, and in-depth epidemiological investigations to understand the reason for increased pathogenicity and different clinical manifestations. These days, ZIKV infection is diagnosed based on clinical manifestations, along with serological and molecular detection tools. As, isolation of ZIKV is a tedious task; molecular assays such as reverse transcription-polymerase chain reaction (RT-PCR), real-time qRT-PCR, loop-mediated isothermal amplification (LAMP), lateral flow assays (LFAs), biosensors, nucleic acid sequence-based amplification (NASBA) tests, strand invasion-based amplification tests and immune assays like enzyme-linked immunosorbent assay (ELISA) are in-use to ascertain the ZIKV infection or Zika fever. Herein, this review highlights the recent advances in the diagnosis, surveillance, and monitoring of ZIKV. These new insights gained from the recent advances can aid in the rapid and definitive detection of this virus and/or Zika fever. The summarized information will aid the strategies to design and adopt effective prevention and control strategies to counter this viral pathogen of great public health concern.

Structures of Zika Virus E & NS1: Relations with Virus Infection and Host Immune Responses

Zika virus (ZIKV), first discovered in the Zika forest in Uganda in 1947 was understudied until the recent explosive epidemic in several South American countries where it has become strongly associated with congenital birth defects leading to severe cranial malformations and neurological conditions. The increase in number of case of microcephaly in newborn children associated with ZIKV infection triggered the World Health Organization to declare the epidemic as a Public Health Emergency of International Concern in February of 2016. ZIKV is a member of the flavivirus genus and is transmitted by Aedes aegypti mosquitoes, however in the current epidemic clear evidence is emerging to suggest the virus can be sexually transmitted from human to human. The differences in epidemiology and manifestations of ZIKV infection during these outbreaks have prompted researchers to investigate mechanisms of dissemination, pathogenesis, and host immune response which contributes significantly to the control of the virus infection. The E and NS1 proteins of ZIKV are the major targets for neutralizing and protective antibodies. In this chapter, we mainly focus on recent research on the crystal structures of the ZIKV E and NS1 proteins, and their relations with virus infection and immune responses. These studies will be helpful to develop novel therapeutics and vaccines for protection and control of ZIKV infection.

Transcriptional Changes during Naturally Acquired Zika Virus Infection Render Dendritic Cells Highly Conducive to Viral Replication

Although dendritic cells are among the human cell population best equipped for cell-intrinsic antiviral immune defense, they seem highly susceptible to infection with the Zika virus (ZIKV). Using highly purified myeloid dendritic cells isolated from individuals with naturally acquired acute infection, we here show that ZIKV induces profound perturbations of transcriptional signatures relative to healthy donors. Interestingly, we noted a remarkable downregulation of antiviral interferon-stimulated genes and innate immune sensors, suggesting that ZIKV can actively suppress interferon-dependent immune responses. In contrast, several host factors known to support ZIKV infection were strongly upregulated during natural ZIKV infection; these transcripts included AXL, the main entry receptor for ZIKV; SOCS3, a negative regulator of ISG expression; and IDO-1, a recognized inducer of regulatory T cell responses. Thus, during in vivo infection, ZIKV can transform the transcriptome of dendritic cells in favor of the virus to render these cells highly conducive to ZIKV infection.

Emerging and reemerging arboviruses: A new threat in Eastern Peru

Background

Arboviral diseases are one of the most common causes of acute febrile illness (AFI) and a significant health problem in South America. In Peru, laboratory etiologic identification of these infections occurs in less than 50% of cases, leading to underdiagnoses of important emerging arboviruses.

Aim

To assess the prevalence of the Dengue (DENV), Oropouche (OROV), Chikungunya (CHIKV), Mayaro (MAYV) and Zika (ZIKV) viruses in patients with acute febrile illness from Puerto Maldonado (Peru).

Methodology

Serum samples were obtained from patients with AFI during January 2016 to March 2016. A total of 139 specimens were analyzed for the presence of DENV, OROV, CHIKV, MAYV, and ZIKV using polymerase chain reaction (PCR).

Results

CHIKV in 9.4% and OROV in 8.6% were the most prevalent arboviruses, followed by DENV and ZIKV, with a prevalence of 6.5% and 5%, respectively. Among all patients, the most common symptoms accompanying fever were headaches 79.9%, muscle pain 65.5% and joint pain 63.3%.

Conclusions

During this short 3-month period, 4 arboviruses were detected by PCR, CHIKV and OROV being the most common arboviruses in Puerto Maldonado (Peru). Thus, it is crucial to include OROV detection in the national health surveillance. Furthermore, the etiologic clinical diagnosis of arboviral infections is not possible due to the low specificity of symptoms; therefore an increase of cases confirmed by molecular diagnostic methods will enhance arboviral surveillance in Peru.

Zika Virus: What Pediatric Emergency Medicine Physicians Need to Know

Zika virus is a mosquito-borne Flavivirus. It has emerged as an important infectious agent in the recent past, mainly because of its teratogenic effects on the fetus. This review highlights the epidemiology, diagnosis, and treatment of this emerging infection.

Rapid colorimetric detection of Zika virus from serum and urine specimens by reverse transcription loop-mediated isothermal amplification (RT-LAMP)

Zika virus (ZIKV) has emerged as a major global public health concern in the last two years due to its link as a causative agent of human birth defects. Its rapid expansion into the Western Hemisphere as well as the ability to be transmitted from mother to fetus, through sexual transmission and possibly through blood transfusions has increased the need for a rapid and expansive public health response to this unprecedented epidemic. A non-invasive and rapid ZIKV diagnostic screening assay that can be performed in a clinical setting throughout pregnancy is vital for prenatal care of women living in areas of the world where exposure to the virus is possible. To meet this need we have developed a sensitive and specific reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) assay to detect ZIKV RNA in urine and serum with a simple visual detection. RT-LAMP results were shown to have a limit of detection 10-fold higher than qRT-PCR. As little as 1.2 RNA copies/μl was detected by RT-LAMP from a panel of 178 diagnostic specimens. The assay was shown to be highly specific for ZIKV RNA when tested with diagnostic specimens positive for dengue virus (DENV) and chikungunya virus (CHIKV). The assay described here illustrates the potential for a fast, reliable, sensitive and specific assay for the detection of ZIKV from urine or serum that can be performed in a clinical or field setting with minimal equipment and technological expertise.

How does Zika virus cause microcephaly?

Here, Wen et al. review the current knowledge and progress in understanding the impact of Zika virus exposure on mammalian brain development and discuss potential underlying mechanisms.

The re-emergence of Zika virus (ZIKV), a mosquito-borne and sexually transmitted flavivirus circulating in >70 countries and territories, poses a significant global threat to public health due to its ability to cause severe developmental defects in the human brain, such as microcephaly. Since the World Health Organization declared the ZIKV outbreak a Public Health Emergency of International Concern, remarkable progress has been made to gain insight into cellular targets, pathogenesis, and underlying biological mechanisms of ZIKV infection. Here we review the current knowledge and progress in understanding the impact of ZIKV exposure on the mammalian brain development and discuss potential underlying mechanisms.

A unique case of human Zika virus infection in association with severe liver injury and coagulation disorders

Zika virus (ZIKV) has caused major concern globally due to its rapid dissemination and close association with microcephaly in children and Gullian-Barr syndrome in adults. In this study, we identified a patient returned from Cambodia who experienced high fever, chill and myalgia. Lab tests discovered sign of severe liver injury including significantly elevated serum transaminases’ level, decreased serum albumin level, and markedly increased levels of lactic dehydrogenase, alpha-hydroxybutyric dehydrogenase and creatine kinase in serum. Moreover, severe thrombocytopenia and altered blood levels of fibrinogen and fibrinogen degradation product were also observed, indicating the existence of clotting disorders. A ZIKV strain clustered into the Asian lineage was isolated from the patient’s serum. When inoculated into suckling mice, this virus significantly retarded mouse body-weight gain and caused 70% mortality. Our results demonstrate a close association between ZIKV and severe liver injury and coagulation disorders and suggest that clinicians should be aware of compatible symptoms in patients and manage them accordingly.