Congenital Zika Syndrome Research Articles

Decreased left atrial volume and preserved left atrial function in children with congenital Zika syndrome

Abstract Introduction The infection caused by Zika virus during pregnancy leads to congenital Zika syndrome (CZS). In a previous study of our group, we found that the heart is smaller in children with CZS, with few functional alterations. Left atrial strain imaging enables quantitative assessment of left atrial function, and recently its application has also shown promise in the pediatric population. Purpose To evaluate left atrial function in children affected by CZS, using echocardiogram and speckle tracking imaging technique. Methods This observational study was conducted with children with CZS using a two-dimensional speckle tracking technique to measure left atrial reservoir strain (LAS-r), conduit strain (LAS-cd), and contraction strain (LAS-ct). Also, to investigate the relationship between LAS-r and systolic excursion of the septum and lateral mitral annular plane (MAPSE), left atrial volume index and E/e’ ratio. Results A total of 52 patients were included, the median age of the studied population was 5 years (3 to 6), 59.6% male, and the body surface area was 0.66 [0.51, 0.90]. In the echocardiographic evaluation the left atrium volume index (ml/m²) was 13.15 [6.80, 18.00], considered smaller by the reference value. Also, the LAS-r (%) was 40.99 [24-70.5], LAS-cd (%) was 30,94 [32.5-52.5], LAS-cd (%) was 10,91 [5.2-24], values considered normal by the literature. Lateral MAPSE (cm) was 1.25 [0.81, 1.86] and septal MAPSE (cm) was 0.98 [0.78, 1.66] and E/e' ratio was 7.52 [4.57, 10.78]. A positive linear correlation was found between LAS-r and lateral MAPSE (r = 0.51, P = 0.019). Conclusion This original study with children with CZS shows that despite reduced atrial volume, the left atrial function remains normal, and correlates with left ventricular function evaluated by MAPSE. Further studies are needed to prospectively analyze the follow-up of left atrial morphology and function in this population.

8624 Maternal ZIKV Infection Causes Oxidative Damage in Placenta of Both Female and Male Mice

Abstract Disclosure: V.M. Nascimento: None. I.S. Andrade: None. C.B. Andrade: None. R.S. Alves: None. R.P. Sousa: None. A.C. Valim: None. L.S. Dias: None. K.N. Fontes: None. I.F. Miranda: None. S.A. Coelho: None. L.B. Arruda: None. R.S. Fortunato: None. T.M. Ortiga-Carvalho: None. The placenta is a maternal-fetal organ with nutritional, exchanging, hormonal and protecting functions that are vital for fetal growth and development during gestation. However, these functions can be disturbed by vertically transmitted pathogens such as Zika virus (ZIKV). In 2015, ZIKV was responsible for an increasing number of newborns with congenital abnormalities in Brazil, known as Congenital Zika Syndrome (CZS). Nonetheless, the extension of ZIKV infection in the placenta, leading to CZS, is still unclear. It is known that ZIKV causes oxidative stress in trophoblasts. However, no one has ever studied placental oxidative stress caused by ZIKV infection in vivo. Here, we investigated whether maternal ZIKV infection could cause sex-specific oxidative stress in murine placenta. At gestational day (GD)12.5, pregnant mice (C57BL/6; 8-12 weeks old) were infected with ZIKV-BRPE243 (5x107 PFU; ZIKV group, n=22) or Mock (supernatants of noninfected C6/36 cells; control group, n=28). At GD18.5, c-section was performed and maternal spleens, placentas, fetuses and fetal brains were collected. We measured placental carbonylated protein levels (n=7), by 2D OxyBlot, nitrotyrosine residues (n=5), by immunohistochemistry, reduced thiol content (n=9), total superoxide dismutase (SOD; n=9) and total glutathione peroxidase (GPx; n=9) activities, by spectrophotometry. Data were analyzed by unpaired Student’s t test and Two-Way ANOVA with Tukey’s post test and represented as mean±SEM. ZIKV infection increased maternal spleen weight (p<0.0001) and decreased both female (p=0.0429) and male (p=0.0171) placental weight. Although placental weights were affected by the infection, female and male fetal weight and fetal crown-rump length were not changed. Conversely, maternal ZIKV infection increased only female fetal brain weight (p=0.0028). Moreover, we found that ZIKV infection increased nitrotyrosine residues in the placental labyrinth region of both female (p<0.0001) and male (p=0.0007) fetuses. Meanwhile, nitrotyrosine residues were increased by the infection only in the placental junctional zone of female fetuses (p=0.0131). Although ZIKV increased this oxidative damage biomarker, placental carbonylated protein levels were not changed by the infection in both sexes. Also, reduced thiol content and total SOD and GPx activities were not affected. Together, our data show that maternal ZIKV infection caused oxidative stress in both placental regions of female and male fetuses, as we saw that ZIKV increased oxidative damage, although antioxidant defenses were not changed by the infection, at least at term (GD18.5). ZIKV infection may have disturbed placental growth, as we found that placental weight was decreased in both sexes. Moreover, we believe that the increase in the female fetal brain weight could be a suggestive feature of cerebral edema or hydrocephalus. Presentation: 6/2/2024

8624 Maternal ZIKV Infection Causes Oxidative Damage in Placenta of Both Female and Male Mice

Abstract Disclosure: V.M. Nascimento: None. I.S. Andrade: None. C.B. Andrade: None. R.S. Alves: None. R.P. Sousa: None. A.C. Valim: None. L.S. Dias: None. K.N. Fontes: None. I.F. Miranda: None. S.A. Coelho: None. L.B. Arruda: None. R.S. Fortunato: None. T.M. Ortiga-Carvalho: None. The placenta is a maternal-fetal organ with nutritional, exchanging, hormonal and protecting functions that are vital for fetal growth and development during gestation. However, these functions can be disturbed by vertically transmitted pathogens such as Zika virus (ZIKV). In 2015, ZIKV was responsible for an increasing number of newborns with congenital abnormalities in Brazil, known as Congenital Zika Syndrome (CZS). Nonetheless, the extension of ZIKV infection in the placenta, leading to CZS, is still unclear. It is known that ZIKV causes oxidative stress in trophoblasts. However, no one has ever studied placental oxidative stress caused by ZIKV infection in vivo. Here, we investigated whether maternal ZIKV infection could cause sex-specific oxidative stress in murine placenta. At gestational day (GD)12.5, pregnant mice (C57BL/6; 8-12 weeks old) were infected with ZIKV-BRPE243 (5x107 PFU; ZIKV group, n=22) or Mock (supernatants of noninfected C6/36 cells; control group, n=28). At GD18.5, c-section was performed and maternal spleens, placentas, fetuses and fetal brains were collected. We measured placental carbonylated protein levels (n=7), by 2D OxyBlot, nitrotyrosine residues (n=5), by immunohistochemistry, reduced thiol content (n=9), total superoxide dismutase (SOD; n=9) and total glutathione peroxidase (GPx; n=9) activities, by spectrophotometry. Data were analyzed by unpaired Student’s t test and Two-Way ANOVA with Tukey’s post test and represented as mean±SEM. ZIKV infection increased maternal spleen weight (p<0.0001) and decreased both female (p=0.0429) and male (p=0.0171) placental weight. Although placental weights were affected by the infection, female and male fetal weight and fetal crown-rump length were not changed. Conversely, maternal ZIKV infection increased only female fetal brain weight (p=0.0028). Moreover, we found that ZIKV infection increased nitrotyrosine residues in the placental labyrinth region of both female (p<0.0001) and male (p=0.0007) fetuses. Meanwhile, nitrotyrosine residues were increased by the infection only in the placental junctional zone of female fetuses (p=0.0131). Although ZIKV increased this oxidative damage biomarker, placental carbonylated protein levels were not changed by the infection in both sexes. Also, reduced thiol content and total SOD and GPx activities were not affected. Together, our data show that maternal ZIKV infection caused oxidative stress in both placental regions of female and male fetuses, as we saw that ZIKV increased oxidative damage, although antioxidant defenses were not changed by the infection, at least at term (GD18.5). ZIKV infection may have disturbed placental growth, as we found that placental weight was decreased in both sexes. Moreover, we believe that the increase in the female fetal brain weight could be a suggestive feature of cerebral edema or hydrocephalus. Presentation: 6/2/2024

The Human Neural Cell Atlas of Zika Infection in developing human brain tissue: viral pathogenesis, innate immunity, and lineage reprogramming.

Zika virus (ZIKV) infection during pregnancy can lead to fetal brain infection and developmental anomalies collectively known as congenital Zika syndrome (CZS). To define the molecular features underlying CZS in a relevant human cell model, we evaluated ZIKV infection and neurodevelopment in primary fetal brain explants and induced pluripotent stem cell-derived mixed neural cultures at single cell resolution. We identified astrocytes as key innate immune sentinel cells detecting ZIKV and producing IFN-β. In contrast, neural progenitor cells displayed impaired innate immunity and supported high levels of viral replication. ZIKV infection of neurons suppressed differentiation and synaptic signaling networks and programmed a molecular switch from neurogenesis to astrogliogenesis. We identified a universal ZIKV-driven cellular stress response linked to intrinsic apoptosis and regulated by IFN-β. These findings reveal how innate immune signaling intersects with ZIKV-driven perturbations in cellular function to influence CZS outcomes including neuron developmental dysfunction and apoptotic cell death.

Distinct Replication Kinetics, Cytopathogenicity, and Immune Gene Regulation in Human Microglia Cells Infected with Asian and African Lineages of Zika Virus.

Zika virus (ZIKV), a mosquito-borne flavivirus, is a significant global health concern due to its association with neurodevelopmental disorders such as congenital Zika syndrome (CZS). This study aimed to compare the replication kinetics, viral persistence, cytopathogenic effects, and immune gene expression in human microglia cells (CHME-3) infected with an Asian lineage ZIKV (PRVABC59, referred to as ZIKV-PRV) and an African lineage ZIKV (IBH30656, referred to as ZIKV-IBH). We found that ZIKV-PRV replicated more efficiently and persisted longer while inducing lower levels of cell death and inflammatory gene activation compared with ZIKV-IBH. These findings suggest that the enhanced replication and persistence of ZIKV-PRV, along with its ability to evade innate immune responses, may underlie its increased neuropathogenic potential, especially in the context of CZS. In contrast, ZIKV-IBH, with its stronger immune gene activation and higher cytopathogenicity, may lead to more acute infections with faster viral clearance, thereby reducing the likelihood of chronic central nervous system (CNS) infection. This study provides crucial insights into the molecular and cellular mechanisms driving the differential pathogenicity of ZIKV lineages and highlights the need for further research to pinpoint the viral factors responsible for these distinct clinical outcomes.

3D Head Shape Feature Analysis of Zika-Infected Children.

Congenital Zika syndrome (CZS) has been identified a constellation of congenital anomalies caused by Zika Virus (ZKV) infection during pregnancy. The infection with ZKV could lead to microcephaly of the fetus due to a severe decrease in brain volume and reduced brain growth. The preliminary screening of CZS is based on measuring head circumference; the diagnosis is made if this measurement is below two standard deviations below the mean. The analyses of the 3D head features of infected infants are limited. This study analyzed 3D head images of 35 ZKV-positive cases with an average age of 16.8 ± 2 months and 35 controls with an average age of 14.4 ± 5 months. This study focused on identifying potential diagnostic characteristics of CZS. The 3D head images were captured using a 3D imaging system. The averaged images of the two groups were aligned to illustrate the size and shape differences. There were significant differences in centroid size, head circumference (HC), head height (HH), and chin height (CH) between the two groups. We also identified significant differences in the indices of chin height/total facial height (CH/TFH) and head height/head circumference ratio (HH/HC) between the CZS and control cases. An HH/HC of 0.49 showed a sensitivity of 0.86 and a specificity of 0.74 in diagnosing CZS, which is more sensitive than the routinely used HC measurement. The index of HH/HC has potential to be used as the gold standard for the early screening for the detection of CZS cases.

Envelope Protein-Targeting Zika Virus Entry Inhibitors.

Zika virus (ZIKV; family, Flaviviridae), which causes congenital Zika syndrome, Guillain-Barré Syndrome, and other severe diseases, is transmitted mainly by mosquitoes; however, the virus can be transmitted through other routes. Among the three structural and seven nonstructural proteins, the surface envelope (E) protein of ZIKV plays a critical role in viral entry and pathogenesis, making it a key target for the development of effective entry inhibitors. This review article describes the life cycle, genome, and encoded proteins of ZIKV, illustrates the structure and function of the ZIKV E protein, summarizes E protein-targeting entry inhibitors (with a focus on those based on natural products and small molecules), and highlights challenges that may potentially hinder the development of effective inhibitors of ZIKV infection. Overall, the article will provide useful guidance for further development of safe and potent ZIKV entry inhibitors targeting the viral E protein.

Ad26.M.Env ZIKV vaccine protects pregnant rhesus macaques and fetuses against Zika virus infection

At the start of the Zika virus (ZIKV) epidemic in 2015, ZIKV spread across South and Central America, and reached parts of the southern United States placing pregnant women at risk for fetal microcephaly, fetal loss, and other adverse pregnancy outcomes associated with congenital ZIKA syndrome (CZS). For this reason, testing of a safe and efficacious ZIKV vaccine remains a global health priority. Here we report that a single immunization with Ad26.M.Env ZIKV vaccine, when administered prior to conception, fully protects pregnant rhesus macaques from ZIKV viral RNA in blood and tissues with no adverse effects in dams and fetuses. Furthermore, vaccination prevents ZIKV distribution to fetal tissues including the brain. ZIKV associated neuropathology was absent in offspring of Ad26.M.Env vaccinated dams, although pathology was limited in fetuses from non-immunized, challenged dams. Vaccine efficacy is associated with induction of ZIKV neutralizing antibodies in pregnant rhesus macaques. These data suggest the feasibility of vaccine prevention of CZS in humans.

The overlapping diagnosis of congenital Zika syndrome and cerebral palsy.

The overlapping diagnosis of congenital Zika syndrome and cerebral palsy.

Manifestações clínicas e o manejo da infecção congênita pelo Zika Vírus: Uma revisão sistemática

Objective: The general objective of the present study is to analyze the scientific production on Congenital Zika Virus Infection, seeking to identify the main clinical manifestations, as well as the main methods used in the treatment of this pathology. Methodology: It is a systematic review focused on understanding the main aspects of Congenital Zika Virus Infection. The research was guided by the question: "What are the main signs and symptoms of congenital Zika virus infection in the pediatric population, as well as what are the therapeutic resources used in clinical practice?" . To find answers, searches were performed in the PubMed database using three descriptors combined with the Boolean term "AND". This resulted in 010 articles. 12 articles were selected for analysis. Results: Congenital Zika syndrome (CZS) emerges as a complex and multifaceted challenge whose implications go beyond the boundaries of public health. Babies exposed to the Zika virus during pregnancy face a range of clinical manifestations, from microcephaly to eye anomalies and neurological disorders. Prevention, therefore, takes on a crucial role: educating pregnant women about the risks and promoting protective measures, such as the use of repellents and mosquito nets, is imperative. Conclusion: Although we do not yet have a licensed Zika vaccine, research efforts continue to explore this possibility. In addition, long-term surveillance is essential to fully understand the effects of the virus. In this scenario, awareness, interdisciplinary collaboration, and a commitment to the well-being of future generations are our best allies in the fight against this potentially devastating syndrome.

Assessment and Prognostic Resources for Gross Motor Development in a Child with Cerebral Palsy Related to Congenital Zika Syndrome.

This article describes how the Gross Motor Ability Estimator (GMAE) software can provide important information based on the Gross Motor Function Measure (GMFM)-66 score of a child with congenital Zika syndrome.A child was assessed at 9, 17, and 25 months of age through the GMFM-66. At 2 years, the child's gross motor ability was estimated and classified according to the Gross Motor Function Classification System (GMFCS).At 2 years of age, the child in this case required assistance to roll and was unable to maintain antigravity trunk posture in sitting position, typical abilities of GMFCS level V.GMAE can be useful to guide health professionals that care for children with lifelong physical and developmental care needs. This is the first study that demonstrated how to use the GMAE in this specific population.

Zika virus vertical transmission induces neuroinflammation and synapse impairment in brain cells derived from children born with Congenital Zika Syndrome

Zika virus (ZIKV) infection was first reported in 2015 in Brazil as causing microcephaly and other developmental abnormalities in newborns, leading to the identification of Congenital Zika Syndrome (CZS). Viral infections have been considered an environmental risk factor for neurodevelopmental disorders outcome, such as Autism Spectrum Disorder (ASD). Moreover, not only the infection per se, but maternal immune system activation during pregnancy, has been linked to fetal neurodevelopmental disorders. To understand the impact of ZIKV vertical infection on brain development, we derived induced pluripotent stem cells (iPSC) from Brazilian children born with CZS, some of the patients also being diagnosed with ASD. Comparing iPSC-derived neurons from CZS with a control group, we found lower levels of pre- and postsynaptic proteins and reduced functional synapses by puncta co-localization. Furthermore, neurons and astrocytes derived from the CZS group showed decreased glutamate levels. Additionally, the CZS group exhibited elevated levels of cytokine production, one of which being IL-6, already associated with the ASD phenotype. These preliminary findings suggest that ZIKV vertical infection may cause long-lasting disruptions in brain development during fetal stages, even in the absence of the virus after birth. These disruptions could contribute to neurodevelopmental disorders manifestations such as ASD. Our study contributes with novel knowledge of the CZS outcomes and paves the way for clinical validation and the development of potential interventions to mitigate the impact of ZIKV vertical infection on neurodevelopment.

Feeding practices and weight status of children with congenital Zika syndrome: A longitudinal study in Brazil.

The objective of this study was to describe feeding practices and weight status in a cohort of children with congenital Zika syndrome (CZS) in northeastern Brazil. This longitudinal study of children with CZS (N = 156) included data collection on child feeding practices and weight status at five timepoints between 2018 and 2022. The average age of the children was 32.1 months at enrollment and 76.6 months at the fifth assessment. Multilevel models, with repeated observations nested within children, were used to estimate time-related differences in each outcome. Use of enteral feeding, such as gastrostomy, increased from 19.2% to 33.3% over 4 years (p < .001). Among children who did not exclusively use an enteral feeding method, the percentage experiencing at least one dysphagia-associated behavior, such as coughing or gagging, increased from 73.9% to 85.3% (p = .030) while consuming liquids and from 36.2% to 73.5% (p = .001) while consuming solids. Based on weight-for-age z-scores, the percentage of children who were moderately or severely underweight increased from 42.5% to 46.1% over the 4 years but was not statistically significant. Children exclusively using an enteral feeding method had significantly decreased odds of being underweight at assessments 3, 4, and 5. These data highlight the ongoing and increasing challenges of feeding young children with CZS. Our findings elucidate the physiological reasons children with CZS may be underweight and point to intervention targets, such as enteral feeding, to improve their feeding practices.

C-FLIP facilitates ZIKV infection by mediating caspase-8/3-dependent apoptosis.

c-FLIP functions as a dual regulator of apoptosis and inflammation, yet its implications in Zika virus (ZIKV) infection remain partially understood, especially in the context of ZIKV-induced congenital Zika syndrome (CZS) where both apoptosis and inflammation play pivotal roles. Our findings demonstrate that c-FLIP promotes ZIKV infection in placental cells and myeloid-derived macrophages, involving inflammation and caspase-8/3-mediated apoptosis. Moreover, our observations reveal that c-FLIP augments ZIKV infection in multiple tissues, including blood cell, spleen, uterus, testis, and the brain of mice. Notably, the partial deficiency of c-FLIP provides protection to embryos against ZIKV-induced CZS, accompanied by a reduction in caspase-3-mediated apoptosis. Additionally, we have found a distinctive parental effect of c-FLIP influencing ZIKV replication in fetal heads. In summary, our study reveals the critical role of c-FLIP as a positive regulator in caspase-8/3-mediated apoptosis during ZIKV infection, significantly contributing to the development of CZS.

Sex-specific effect of antenatal Zika virus infection on murine fetal growth, placental nutrient transporters, and nutrient sensor signaling pathways.

Maternal Zika virus (ZIKV) infection during pregnancy has been associated with severe intrauterine growth restriction (IUGR), placental damage, metabolism disturbances, and newborn neurological abnormalities. Here, we investigated the impact of maternal ZIKV infection on placental nutrient transporters and nutrient-sensitive pathways. Immunocompetent (C57BL/6) mice were injected with Low (103 PFU-ZIKVPE243) or High (5 × 107 PFU-ZIKVPE243) ZIKV titers at gestational day (GD) 12.5, and tissue was collected at GD18.5 (term). Fetal-placental growth was impaired in male fetuses, which exhibited higher placental expression of the ZIKV infective marker, eukaryotic translation initiation factor 2 (eIF2α), but lower levels of phospho-eIF2α. There were no differences in fetal-placental growth in female fetuses, which exhibited no significant alterations in placental ZIKV infective markers. Furthermore, ZIKV promoted increased expression of glucose transporter type 1 (Slc2a1/Glut1) and decreased levels of glucose-6-phosphate in female placentae, with no differences in amino acid transport potential. In contrast, ZIKV did not impact glucose transporters in male placentae but downregulated sodium-coupled neutral amino acid 2 (Snat2) transporter expression. We also observed sex-dependent differences in the hexosamine biosynthesis pathway (HBP) and O-GlcNAcylation in ZIKV-infected pregnancies, showing that ZIKV can disturb placental nutrient sensing. Our findings highlight molecular alterations in the placenta caused by maternal ZIKV infection, shedding light on nutrient transport, sensing, and availability. Our results also suggest that female and male placentae employ distinct coping mechanisms in response to ZIKV-induced metabolic changes, providing insights into therapeutic approaches for congenital Zika syndrome.

Long-term developmental outcomes of children with congenital Zika syndrome.

Eight years after the epidemics in Brazil, children with congenital Zika syndrome (CZS) and their families confront ongoing health challenges. This study aims to characterize how virally induced prenatal brain injury impacts development and functional outcomes among children diagnosed with CZS. We performed a cross-sectional study of a consecutive series of children diagnosed with CZS. Using validated neurodevelopmental assessments, we evaluated gross motor function, manual ability, communication, eating and drinking, and visual function. Sixty children (29 males, and 31 females) met the inclusion criteria for the study. Comorbidities such as epilepsy (90.0%) and undernutrition (38.3%), along with clinical conditions including dysphagia (68.3%) and dependence on tube feeding (31.7%), were observed. Our results demonstrate a majority of children at level V - the most severe level within a five-tier system - in the Gross Motor Function (86.7%), Manual Ability (85.0%), Communication Function (68.3%), Eating and Drinking Ability (40.0%) Classification Systems, and level IV in the Visual Function Classification System (38.3%). CZS is associated with severe functional impairments and comorbidities, adversely impacting child development and quality of life. These findings reveal persistent challenges affecting the functioning of children with CZS, underscoring the need for continued support and specialized care. This study aimed to characterize the long-term clinical and functional characteristics of a subset of children with Congenital Zika Syndrome (CZS). We found that eight years after the Brazilian Zika epidemic, this subset of children with CZS continues to demonstrate major functional limitations impacting mobility, vision, and the ability to eat and drink. Our analysis documented a very high level of disability in several key functional classification systems. Notably, applying a new instrument for visual ability among children diagnosed with cerebral palsy, we found that more than 60% of the study group have poor or very poor visual function.

Evaluation of the effects of the Zika Virus-Immunoglobulin G+ complex on murine microglial cells.

After the Zika virus (ZIKV) epidemic in Brazil, ZIKV infections were linked to damage to the central nervous system (CNS) and congenital anomalies. Due to the virus's ability to cross the placenta and reach brain tissue, its effects become severe, leading to Congenital Zika Syndrome (CZS) and resulting in neuroinflammation, microglial activation, and secretion of neurotoxic factors. The presence of ZIKV triggers an inadequate fetal immune response, as the fetus only has the protection of maternal antibodies of the Immunoglobulin G (IgG) class, which are the only antibodies capable of crossing the placenta. Because of limited understanding regarding the long term consequences of ZIKV infection and the involvement of maternal antibodies, this study sought to assess the impact of the ZIKV + IgG⁺complex on murine microglial cells. The cells were exposed to ZIKV, IgG antibodies, and the ZIKV + IgG⁺complex for 24 and 72h. Treatment-induced cytotoxic effects were evaluated using the cell viability assay, oxidative stress, and mitochondrial membrane potential. The findings indicated that IgG antibodies exhibit cytotoxic effects on microglia, whether alone or in the presence of ZIKV, leading to compromised cell viability, disrupted mitochondrial membrane potential, and heightened oxidative damage. Our conclusion is that IgG antibodies exert detrimental effects on microglia, triggering their activation and potentially disrupting the creation of a neurotoxic environment. Moreover, the presence of antibodies may correlate with an elevated risk of ZIKV-induced neuroinflammation, contributing to long-term CNS damage.

Neurodevelopmental Outcomes of Preschoolers with Antenatal Zika Virus Exposure Born in the United States.

Neurodevelopmental outcomes for preschool-age children in the United States with in utero Zika virus (ZIKV) exposure have not yet been reported. We performed a case-control study to assess whether children exposed in utero to ZIKV have abnormal neurodevelopment at age 4-5 years compared to unexposed controls. Thirteen ZIKV-exposed cases that did not have microcephaly or other specific features of congenital Zika syndrome and 12 controls were evaluated between ages 4-5 years. Child neurodevelopment was assessed using the Pediatric Evaluation of Disability Inventory, Behavior Rating Inventory of Executive Function, Peabody Picture Vocabulary Test, Bracken School Readiness Assessment (BSRA), and Movement Assessment Battery for Children (MABC). Caregivers answered questions on the child's medical history and family demographics. Cases and controls were evaluated at mean (SD) ages 4.9 (0.3) and 4.8 (0.4) years, respectively. Caregivers reported more behavior and mood problems in cases than controls. MABC scores showed more gross and fine motor coordination difficulties among cases than controls. Controls trended towards higher performance on concepts underlying school readiness on BSRA. Three cases had a diagnosis of autism spectrum disorder or global developmental delay. Continued follow-up through school age for children with prenatal ZIKV exposure is needed to understand the impact of in utero ZIKV exposure on motor coordination, cognition, executive function, and academic achievement.

Association between Sleep and Language Development in Children with Congenital Zika Syndrome.

Congenital Zika Virus Syndrome (CZS) presents notable hurdles to neurodevelopment, with language development emerging as a crucial aspect. This study investigates sleep patterns and language skills in children with CZS, aiming to explore the potential synchronization of sleep development with their neurodevelopment. We studied cross-sectionally 135 children with CZS aged 0 to 48 months, investigating sleep using the BISQ Questionnaire. Language development was assessed using the Early Language Milestone Scale, while motor development and cognitive and social ability were assessed using the Bayley Scales of Infant and Young Child Development 3rd edition. We also studied longitudinally a cohort of 16 children (initially aged 0 to 12 months) whom we followed for four years, assessing at one-year intervals. Sleep disturbances and language deficits were highly frequent in this population. In the 0-12 months group, a late bedtime and frequent nighttime awakenings were associated with poorer auditory expressive skills. At 13-24 months, nighttime awakenings were associated with poorer auditory expressive skills, while among 25-36-month-olds decreased auditory receptive skills were associated with longer sleep onset latency and reduced nighttime sleep duration. The brain alterations caused by Zika virus infection affect both sleep disturbances and delays in language development. It is possible that sleep disturbance may be a mediating factor in the pathway between CZS and delayed language development, as the three analyzed language skills showed a correlation with sleep parameters.

Disruption of myelin structure and oligodendrocyte maturation in a macaque model of congenital Zika infection

Zika virus (ZikV) infection during pregnancy can cause congenital Zika syndrome (CZS) and neurodevelopmental delay in infants, of which the pathogenesis remains poorly understood. We utilize an established female pigtail macaque maternal-to-fetal ZikV infection/exposure model to study fetal brain pathophysiology of CZS manifesting from ZikV exposure in utero. We find prenatal ZikV exposure leads to profound disruption of fetal myelin, with extensive downregulation in gene expression for key components of oligodendrocyte maturation and myelin production. Immunohistochemical analyses reveal marked decreases in myelin basic protein intensity and myelinated fiber density in ZikV-exposed animals. At the ultrastructural level, the myelin sheath in ZikV-exposed animals shows multi-focal decompaction, occurring concomitant with dysregulation of oligodendrocyte gene expression and maturation. These findings define fetal neuropathological profiles of ZikV-linked brain injury underlying CZS resulting from ZikV exposure in utero. Because myelin is critical for cortical development, ZikV-related perturbations in oligodendrocyte function may have long-term consequences on childhood neurodevelopment, even in the absence of overt microcephaly.