Congenital Microcephaly Research Articles

E90 subunit vaccine protects mice from Zika virus infection and microcephaly

Zika virus (ZIKV) became a global threat due to its unprecedented outbreak and its association with congenital malformations such as microcephaly in developing fetuses and neonates. There are currently no effective vaccines or drugs available for the prevention or treatment of ZIKV infection. Although multiple vaccine platforms have been established, their effectiveness in preventing congenital microcephaly has not been addressed. Herein, we tested a subunit vaccine containing the 450 amino acids at the N-terminus of the ZIKV envelope protein (E90) in mouse models for either in utero or neonatal ZIKV infection. In one model, embryos of vaccinated dams were challenged with a contemporary ZIKV strain at embryonic day 13.5. The other model infects neonatal mice from vaccinated dams by direct injection of ZIKV into the developing brains. The vaccine led to a substantial reduction of ZIKV-infected cells measured in the brains of fetal or suckling mice, and successfully prevented the onset of microcephaly compared to unvaccinated controls. Furthermore, E90 could protect mice from ZIKV infection even at 140 days post-immunization. This work directly demonstrates that immunization of pregnant mice protects the developing brains of offspring both in utero and in the neonatal period from subsequent ZIKV infection and microcephaly. It also supports the further development of the E90 subunit vaccine towards clinical trials.

Long-term Zika complications

Congenital Zika Syndrome (CZS) has as a main characteristic the brain impairment, with microcephalus, however it is still little known about this entity and its clinical spectrum that includes newborns with normal head circumference. In addition to congenital microcephaly and craniofacial disproportion, a range of manifestations have been associated with CZS, including neurologic symptoms, arthrogryposis, hearing and ocular abnormalities. The neurologic findings of severe affected patients include irritability, hyperexcitability, hypertonia and dysphagia. Regardless of the ophthalmologic impairment, more than a half of the patients with the CZS and severe microcephaly have presented poor interaction with the environment related to cortical impairment. Epilepsy is frequent, even in patients with normal head circumference at birth. The arthrogrypotic joints did not result from abnormalities of the joints themselves and are likely to be of neurogenic origin. The pattern of brain images abnormalities in CZS has been fully described. The pattern of calcifications at the junction between cortical and subcortical white matter, in addition to the cortical developmental disorders predominantly on frontal regions confers highly suggestive pattern of CZS. Cerebellar atrophy and malformations of the brainstem may also occur. Unlike other congenital infections, several patients are developing hydrocephalus between 3 to 18 months. The pathophysiology of hydrocephalus in CZS is still unknown The complete neurological picture requires the central nervous system maturation and it will only become clear after, at least 18 months, so to a better definition of congenital Zika syndrome we need a longer follow-up.

Zika virus from a neonatologist’s perspective

Zika virus has been known for more than half a century. Its clinical significance was just recently discovered, after the epidemic of Zika virus emerged in South and Central America. A task force established in 2015 by the Brazil Ministry of Health investigated the possible association between congenital Zika infection and microcephaly in fetuses and newborns. Since then more and more evidence emerged, supporting this hypothesis. The objective of this article is to review and summarize the currently available literature regarding Zika virus from a neonatologist’s standpoint and provide some guidance to medical providers who may have to care for potentially exposed pregnant patients and their newborns.

A novel SLC1A4 homozygous mutation causing congenital microcephaly, epileptic encephalopathy and spastic tetraparesis: a video-EEG and tractography – case study

Biallelic mutations in the SLC1A4 gene have been identified as a very rare cause of neurodevelopmental disorders. l-serine transport deficiency has been regarded as the causal molecular mechanism underlying the neurological phenotype of SLC1A4 mutation patients. To date this genetic condition has been reported almost exclusively in a limited number of Ashkenazi-Jewish individuals and as a result the SLC1A4 gene is not routinely included in the majority of the genetic diagnostic panels for neurological diseases. We hereby report a 7-year-old boy from a Southern Italian family, presenting with epileptic encephalopathy, congenital microcephaly, global developmental delay, severe hypotonia, spasticity predominant at the lower limbs, and thin corpus callosum. Whole exome sequencing identified a novel segregating SLC1A4 gene homozygous mutation (c.1141G > A: p.Gly381Arg) as the likely cause of the disease in our family. In order to deeply characterize the electro-clinical and neurological phenotype in our index patient, long-term systematic video-electroencephalograms (EEG) as well as repeated brain imaging studies (which included tractographic reconstructions) were performed on a regular basis during a 7 years follow-up time.In conclusion, we suggest to carefully considering SLC1A4 biallelic mutations in individuals presenting an early onset severe neurodevelopmental disorder with variable spasticity and seizures, regardless the patients’ ethnic background.

Prevalence and causes of congenital microcephaly in the absence of a Zika virus outbreak in southern Brazil

ObjectiveThe aim of this study was to identify the causes of congenital microcephaly in Rio Grande do Sul, a state in southern Brazil, where no ZIKV outbreak was detected, from December 2015 to December 2016, which was the period when ZIKV infection was at its peak in northeast Brazil. MethodsThis was a cross-sectional study where all notifications of congenital microcephaly in the state of Rio Grande do Sul were included for analysis. Evaluation of cases followed the guidelines of the Brazilian Ministry of Health. Dysmorphological and neurological evaluations were performed by a specialized team, and genetic tests and neuroimaging were performed when clinically indicated. STORCH infections were diagnosed using standard tests. ZIKV infection was diagnosed through maternal serum RT-PCR and/or neuroimaging associated with clinical/epidemiological criteria. ResultsFrom 153744 registered live births in the study period, 148 cases were notified, but 90 (60.8%) of those were later excluded as “non-confirmed” microcephaly. In the 58 confirmed cases of microcephaly (prevalence = 3.8/10000 live births), congenital infections (syphilis, toxoplasmosis, cytomegalovirus, and ZIKV) constituted the predominant etiology (50.0%), followed by isolated CNS (15.5%), and genetic syndromes (10.3%). Congenital ZIKV syndrome (CZS) with typical phenotype was diagnosed in three cases (5.2% of all confirmed microcephaly cases or 10.4% of all congenital infections). ConclusionIn Rio Grande do Sul, where no outbreak of ZIKV infection was recorded, congenital infections were the leading cause of congenital microcephaly, and the attributable risk for CZS in the etiology of microcephaly was 5.2%.

Clinical and epidemiological aspects of microcephaly in the state of Piauí, northeastern Brazil, 2015–2016

ObjectivesTo describe aspects of the microcephaly epidemic in the state of Piauí. MethodsAll cases of congenital microcephaly confirmed in the state between 2015 and 2016 were included (n=100). Investigation forms of the Regional Reference Center for Microcephaly were reviewed. Discarded cases (n=63) were used as a comparison group. ResultsIn October, November, and December 2015 incidence rates reached 4.46, 6.33 and 3.86/1000 live births, respectively; 44 cases were reported in the state capital. Among the mothers of confirmed and discarded cases, the frequency of skin rash during pregnancy was 50/97 (51.5%) and 8/51 (15.7%), respectively (p<0.001); 33 confirmed cases (35.9%) had a head circumference z-score between −2 and −3, 23 (25%) between −3 and −4, and 8 (8.7%) had a z-score of less than −4. Head computer tomography scans revealed calcifications in 78/95 (82.1%) cases. Lissencephaly, hydrocephalus and agenesis of the corpus callosum were also frequently observed. Ophthalmic findings included retinal pigment epithelium rarefaction and atrophy. Absence of otoacoustic emissions was observed in 21/70 cases. One newborn also presented lower limb muscle atrophy. There were no significant differences in vaccination rates for influenza, diphtheria-tetanus-acellular pertussis, and hepatitis B in either group. ConclusionsThe state of Piauí, like others in the northeastern region, faced an epidemic of congenital microcephaly between 2015 and 2016, presumably related to congenital Zika virus infection, more intense in the capital. Current challenges include the improvement of vector control, basic research, scaling-up of diagnostic tools for pre-natal screening of Zika virus, vaccines, and health care for affected children.

P.067 Phosphoserine aminotransferase (PSAT) deficiency: Imaging findings in a child with congenital microcephaly

Background: Serine deficiency disorders can result from deficiency in one of three enzymes. Deficiency of the second enzyme in the serine biosynthesis pathway, 3-phosphoserine aminotransferase (PSAT), has been reported in two siblings when the eldest was investigated for acquired microcephaly, progressive spasticity and intractable epilepsy. Methods: Our patient had neurological symptoms apparent at birth. Fetal magnetic resonance imaging (MRI) at 35 weeks gestation demonstrated microencephaly and simplification of the the gyration (anterior&gt;posterior) which was confirmed upon subsequent post-natal MRI. Congenital microcephaly was apparent at birth. Results: PSAT deficiency was confirmed when exome sequencing identified biallelic mutations in PSAT1; c.44C&gt;T, p.Ala15Val and; c.432delA, p.Pro144fs and biochemical testing noted low plasma serine 22 mcmol/L (normal 83-212 mcmol/L) and low CSF serine 10 mcmol/L (normal 22-61 mcmol/L). Despite oral serine and glycine supplementation at 4 months old the patient showed little neurodevelopmental progress and developed epileptic spasms at 10 months old. Serological testing for TORCH infections was negative. Conclusions: PSAT deficiency should be considered for patients with congenital microcephaly. Although further characterization of MRI findings in other patients is required, microencephaly with simplified gyral pattern could provide imaging clues for this rare metabolic disorder.

Chromosomal microarray analysis in developmental delay and intellectual disability with comorbid conditions

BackgroundDevelopmental delay (DD) and intellectual disability (ID) are frequently associated with a broad spectrum of additional phenotypes. Chromosomal microarray analysis (CMA) has been recommended as a first-tier test for DD/ID in general, whereas the diagnostic yield differs significantly among DD/ID patients with different comorbid conditions.MethodsTo investigate the genotype-phenotype correlation, we examined the characteristics of identified pathogenic copy number variations (pCNVs) and compared the diagnostic yields among patient subgroups with different co-occurring conditions.ResultsThis study is a retrospective review of CMA results generated from a mixed cohort of 710 Chinese patients with DD/ID. A total of 247 pCNVs were identified in 201 patients (28%). A large portion of these pCNVs were copy number losses, and the size of copy number losses was generally smaller than gains. The diagnostic yields were significantly higher in subgroups with co-occurring congenital heart defects (55%), facial dysmorphism (39%), microcephaly (34%) or hypotonia (35%), whereas co-occurring conditions of skeletal malformation (26%), brain malformation (24%) or epilepsy (24%) did not alter the yield. In addition, the diagnostic yield nominally correlated with ID severity.ConclusionVaried yields exist in DD/ID patients with different phenotypic presentation. The presence of comorbid conditions can be among factors to consider when planning CMA.

The host ubiquitin system in innate immunity and virus replication: proviral and antiviral functions of the host E3-ubiquitin ligase TRIM family

Abstract Type-I Interferons (IFN-I), which are innate immune cytokines with broad-spectrum antiviral effects, are regulated by the host Ubiquitin (Ub) system. Evidence has shown that new forms of poly-Ub chains, which are not covalently attached to any protein (termed unanchored poly-Ub), are important activators of kinase activity in vitro. We recently reported that unanchored K48-linked poly-Ub synthesized by the E3-Ub ligase TRIM6 promote IFN-mediated antiviral innate immunity in vivo by activating the IKKɛ kinase. Intriguingly, we found that two different highly pathogenic viruses, Nipah (NiV; Paramyxoviridae family) and Ebola (EBOV; Filoviridae family), hijack TRIM6 to promote virus replication through mechanisms that involve both covalent and unanchored Ub. This indicates that host antiviral factors can have direct pro-viral functions. We also found that Zika virus (ZIKV; Flaviviridae family), which can cause congenital microcephaly in newborns, requires ubiquitination of viral proteins for efficient replication. Importantly, ZIKV ubiquitination occurs in vivo in a tissue-specific manner. Recombinant infectious ZIKV mutants that lack ubiquitination on specific sites are attenuated in mice and appear to differentially replicate in tissues. As compared to other flaviviruses, ZIKV acquired an additional ubiquitination site, which may be responsible for providing ZIKV an advantage to replicate in brain and reproductive tissue. This would be the first example of a flavivirus utilizing the Ub system for tissue tropism. Taken together, our work suggests that divergent viruses hijack similar innate immune host factors to enhance their replication. This information could help design novel broad-spectrum antiviral strategies

Estimating the numbers of pregnant women infected with Zika virus and infants with congenital microcephaly in Colombia, 2015–2017

Colombia experienced a Zika virus (ZIKV) outbreak in 2015-2016. To assist with planning for medical and supportive services for infants affected by prenatal ZIKV infection, we used a model to estimate the number of pregnant women infected with ZIKV and the number of infants with congenital microcephaly from August 2015 to August 2017. We used nationally reported cases of symptomatic ZIKV disease among pregnant women and information from the literature on the percent of asymptomatic infections to estimate the number of pregnant women with ZIKV infection occurring August 2015-December 2016. We then estimated the number of infants with congenital microcephaly expected to occur August 2015-August 2017. To compare to the observed counts of infants with congenital microcephaly due to all causes reported through the national birth defects surveillance system, the model was time limited to produce estimates for February-November 2016. We estimated 1140-2160 (interquartile range [IQR]) infants with congenital microcephaly in Colombia, during August 2015-August 2017, whereas 340-540 infants with congenital microcephaly would be expected in the absence of ZIKV. Based on the time limited version of the model, for February-November 2016, we estimated 650-1410 infants with congenital microcephaly in Colombia. The 95% uncertainty interval for the latter estimate encompasses the 476 infants with congenital microcephaly reported during that approximate time frame based on national birth defects surveillance. Based on modeled estimates, ZIKV infection during pregnancy in Colombia could lead to 3-4 times as many infants with congenital microcephaly in 2015-2017 as would have been expected in the absence of the ZIKV outbreak. This publication was made possible through support provided by the Bureau for Global Health, U.S. Agency for International Development under the terms of an Interagency Agreement with Centers for Disease Control and Prevention.

The Countermeasure for Zika Virus: A Hard Nut to Be Cracked

The emergence of Zika virus (ZIKV) infection in America has caused a new threat worldwide, as it is linked with the increased incidence of congenital microcephaly in neonates and development of Guillain–Barré syndrome. A number of potential antiviral drugs such as sofosbuvir, BCX4430, NITD008 and 7-DMA have shown activity against ZIKV both in vitro and in vivo. Similarly, different research organizations and academic institutions are trying hard to develop a vaccine against the ZIKV. Some of these groups have received approval from the US FDA to start Phase I clinical trials. Immuno-based treatment strategies, such as use of humanized monoclonal antibodies (hE16 and CR4373) have also entered clinical trials. However, a licensed vaccine is still a long way off and efforts should be made to accelerate the evaluation procedures while minimizing the delay in licensing.

A case of new PCDH12 gene variants presented as dyskinetic cerebral palsy with epilepsy

Here we report a Japanese patient with new compound heterozygous truncating variants in the PCDH12 gene. As compared to the previously reported families who had congenital microcephaly, intrauterine growth retardation, intracranial calcification, and neonatal seizure associated with dysplasia of the midbrain-hypothalamus-optic tract, the present patient showed no midbrain-hypothalamus dysplasia or congenital/postnatal microcephaly, but dyskinetic cerebral palsy and severe intellectual disability as well as multifocal epilepsy. To understand phenotypic spectrum associated with PCDH12 variants, more reports are needed.

Sustained Specific and Cross-Reactive T Cell Responses to Zika and Dengue Virus NS3 in West Africa.

Recent studies on the role of T cells in Zika virus (ZIKV) infection have shown that T cell responses to Asian ZIKV infection are important for protection, and that previous dengue virus (DENV) exposure amplifies the protective T cell response to Asian ZIKV. Human T cell responses to African ZIKV infection, however, remain unexplored. Here, we utilized the modified anthrax toxin delivery system to develop a flavivirus enzyme-linked immunosorbent spot (ELISPOT) assay. Using human ZIKV and DENV samples from Senegal, West Africa, our results demonstrate specific and cross-reactive T cell responses to nonstructural protein 3 (NS3). Specifically, we found that T cell responses to NS3 protease are ZIKV and DENV specific, but responses to NS3 helicase are cross-reactive. Sequential sample analyses revealed immune responses sustained many years after infection. These results have important implications for African ZIKV/DENV vaccine development, as well as for potential flavivirus diagnostics based on T cell responses.IMPORTANCE The recent Zika virus (ZIKV) epidemic in Latin America and the associated congenital microcephaly and Guillain-Barré syndrome have raised questions as to why we have not recognized these distinct clinical diseases in Africa. The human immunologic response to ZIKV and related flaviviruses in Africa represents a research gap that may shed light on the mechanisms contributing to protection. The goal of our study was to develop an inexpensive assay to detect and characterize the T cell response to African ZIKV and DENV. Our data show long-term specific and cross-reactive human immune responses against African ZIKV and DENV, suggesting the usefulness of a diagnostic based on the T cell response. Additionally, we show that prior flavivirus exposure influences the magnitude of the T cell response. The identification of immune responses to African ZIKV and DENV is of relevance to vaccine development.

NLRP3 Inflammasome Activation Mediates Zika Virus-Associated Inflammation.

Zika virus (ZIKV) is a mosquito-borne virus that has been identified as a cause of several severe disease manifestations, including congenital microcephaly and Guillain-Barré syndrome, meningoencephalitis, and myelitis. Previous studies showed that ZIKV-infected patients exhibited elevated plasma levels of interleukin 1β (IL-1β), indicating that ZIKV may activate inflammasomes. However, the molecular basis for its viral pathogenesis remains poorly understood. In this current study, we found that ZIKV infection caused severe inflammatory pathological changes and promoted IL-1β production in vitro and in vivo. We here demonstrate that the maturation and secretion of IL-1β during ZIKV infection was mediated by NLRP3 inflammasome activation and that ZIKV nonstructural protein 5 (NS5) facilitated the assembly of the NLRP3 inflammasome complex, leading to IL-1β activation through interaction with NLRP3 and induction of reactive oxygen species production. Collectively, our data identify NLRP3 inflammasome-derived IL-1β production as a critical feature of inflammation during ZIKV infection. These findings offer new insights into inflammasome-mediated diseases and may provide new therapeutic options for ZIKV-associated diseases.

Efficient detection of Zika virus RNA in patients\u2019 blood from the 2016 outbreak in Campinas, Brazil

Infection with Zika virus (ZIKV), a mosquito-borne flavivirus has been casually linked with increased congenital microcephaly in Brazil from 2015 through 2016. Sensitive and specific diagnosis of patients with Zika fever (ZIKF) remains critical for patient management. We developed a ZIKV NS5 qRT-PCR assay by combining primers described by Balm et al. and a new Taqman probe. The assay was evaluated and compared with another assay described by Lanciotti et al. (ZIKV 1107) using 51 blood and 42 urine samples from 54 suspected ZIKV patients. ZIKV NS5 performed better in terms of sensitivity with more samples detected as ZIKV-positive (n = 37) than ZIKV 1107 (n = 34) for urine, and ZIKV-positive (n = 29) than ZIKV 1107 (n = 26) for blood. Both assays displayed good overall agreement for urine (κappa = 0.770) and blood (κappa = 0.825) samples. Improved availability of validated diagnostic tests, such ZIKV NS5 qRT-PCR, will be critical to ensure adequate and accurate ZIKV diagnosis.

Neurological impairment of the monozygotic twins with congenital infection presumed by Zika virus: Case report

Abstract Introduction: the increase in the incidence of congenital microcephaly in Brazil has been associated to the Zika virus outbreak. This case report aimed to describe the neurological impairment of monozygotic twins presumably due to an intrauterine infection by Zika virus during the Brazilian outbreak in 2015. Case description: The monozygotic twins born at term with severe congenital microcephaly were taken to the Outpatient Pediatric Service of a University Hospital. The 17-yearold mother, primigravida, lives in the Northeast region of Brazil, has a normal body mass index, no family history of microcephaly, no clinical history of viral diseases, or exposure to drugs and/or radiation during pregnancy. Serological tests for toxoplasmosis, rubella, syphilis, cytomegalovirus and HIV were negative at the prenatal evaluation and the obstetrical ultrasounds showed a monochorionic, diamniotic twin pregnancy without any evidence of neurological abnormalities. In the post-natal, the imaging of the skull, was evidenced of a great neurological impairment in one of the twins, who, in addition to presenting cerebral calcifications, gliosis and subependymal cysts, also had ventriculomegaly with hydrocephalus of supratentorial predominance and more pronounced cerebral atrophy compared to the other twin. Both presented delayed neuropsychomotor development. Discussion: distinct neurological alterations in the monochorionic twins with an infection presumed by Zika virus may raise the hypothesis of the existence of predisposing factors or protection against this viral agent.

Zika virus infection estimates, Mexico.

ObjectiveTo assess the magnitude of the Mexican epidemic of Zika virus infection and the associated risk of microcephaly.MethodsFrom the reported number of laboratory-confirmed symptomatic infections among pregnant women and the relevant birth rate, we estimated the number of symptomatic cases of infection that occurred in Mexico between 25 November 2015, when the first confirmed Mexican case was reported, and 20 August 2016. We used data from the birth certificates to compare mean monthly incidences of congenital microcephaly before (1 January 2010–30 November 2015) and after (1 December 2015–30 September 2017) the introduction of Zika virus, stratifying the data according to whether the mother’s place of residence was at an altitude of at least 2200 m above sea level. We used Poisson interrupted time series, statistical modelling and graphical analyses.FindingsOur estimated number of symptomatic cases of infection that may have occurred in the general population of Mexico between 25 November 2015 and 20 August 2016, 60 172, was 7.3-fold higher than the corresponding number of reported cases. The monthly numbers of microcephaly cases per 100 000 live births were significantly higher after the introduction of the virus than before (incidence rate ratio, IRR: 2.9; 95% confidence interval, CI: 2.3 to 3.6), especially among the babies of women living at altitudes below 2200 m (IRR: 3.4; 95% CI: 2.9 to 3.9).ConclusionThe Mexican epidemic appears to be much larger than indicated by estimates based solely on counts of laboratory-confirmed cases, and to be associated with significantly increased risk of microcephaly.

Congenital microcephaly: A diagnostic challenge during Zika epidemics.

The multiple, wide and diverse etiologies of congenital microcephaly are complex and multifactorial. Recent advances in genetic testing have improved understanding of novel genetic causes of congenital microcephaly. The recent Zika virus (ZIKV) epidemic in Latin America has highlighted the need for a better understanding of the underlying pathological mechanisms of microcephaly including both infectious and non-infectious causes. The diagnostic approach to microcephaly needs to include potential infectious and genetic etiologies, as well as environmental in-utero exposures such as alcohol, toxins, and medications. Emerging genetic alterations linked to microcephaly include abnormal mitotic microtubule spindle structure and abnormal function of centrosomes. We discuss the diagnostic challenge of congenital microcephaly in the context of understanding the links with ZIKV emergence as a new etiological factor involved in this birth defect.

Favipiravir and Ribavirin Inhibit Replication of Asian and African Strains of Zika Virus in Different Cell Models.

Zika virus (ZIKV) has recently emerged as a new public health threat. ZIKV infections have caused a wide spectrum of neurological diseases, such as Guillain–Barré syndrome, myelitis, meningoencephalitis, and congenital microcephaly. No effective therapies currently exist for treating patients infected with ZIKV. Herein, we evaluated the anti-viral activity of favipiravir (T-705) and ribavirin against Asian and African strains of ZIKV using different cell models, including human neuronal progenitor cells (hNPCs), human dermal fibroblasts (HDFs), human lung adenocarcinoma cells (A549) and Vero cells. Cells were treated with favipiravir or ribavirin and effects on ZIKV replication were determined using quantitative real-time PCR and plaque assay. Our results demonstrate that favipiravir or ribavirin treatment significantly inhibited ZIKV replication in a dose-dependent manner. Moreover, favipiravir treatment of ZIKV-infected hNPCs led to reduced cell death, enhanced AKT pathway phosphorylation, and increased expression of anti-apoptotic factor B cell lymphoma 2. In conclusion, our results demonstrate conclusively that favipiravir inhibits ZIKV replication and prevents cell death, and can be a promising intervention for ZIKV-associated disease.

Clinical assessment and brain findings in a cohort of mothers, fetuses and infants infected with ZIKA virus

Congenital Zika virus (ZIKV) infection can be detected in both the presence and absence of microcephaly and manifests as a number of signs and symptoms that are detected clinically and by neuroimaging. However, to date, qualitative and quantitative measures for the purpose of diagnosis and prognosis are limited. Main objectives of this study conducted on fetuses and infants with confirmed congenital Zika virus infection and detected brain abnormalities were (1) to assess the prevalence of microcephaly and the frequency of the anomalies that include a detailed description based on ultrasound and magnetic resonance imaging in fetuses and ultrasound, magnetic resonance imaging, and computed tomography imaging postnatally, (2) to provide quantitative measures of fetal and infant brain findings by magnetic resonance imaging with the use of volumetric analyses and diffusion-weighted imaging, and (3) to obtain additional information from placental and fetal histopathologic assessments and postnatal clinical evaluations. This is a longitudinal cohort study of Zika virus-infected pregnancies from a single institution in Colombia. Clinical and imaging findings of patients with laboratory-confirmed Zika virus infection and fetal brain anomalies were the focus of this study. Patients underwent monthly fetal ultrasound scans, neurosonography, and a fetal magnetic resonance imaging. Postnatally, infant brain assessment was offered by the use of ultrasound imaging, magnetic resonance imaging, and/or computed tomography. Fetal head circumference measurements were compared with different reference ranges with <2 or <3 standard deviations below the mean for the diagnosis of microcephaly. Fetal and infant magnetic resonance imaging images were processed to obtain a quantitative brain volumetric assessment. Diffusion weighted imaging sequences were processed to assess brain microstructure. Anthropometric, neurologic, auditory, and visual assessments were performed postnatally. Histopathologic assessment was included if patients opted for pregnancy termination. All women (n=214) had been referred for Zika virus symptoms during pregnancy that affected themselves or their partners or if fetal anomalies that are compatible with congenital Zika virus syndrome were detected. A total of 12 pregnant patients with laboratory confirmation of Zika virus infection were diagnosed with fetal brain malformations. Most common findings that were assessed by prenatal and postnatal imaging were brain volume loss (92%), calcifications (92%), callosal anomalies (100%), cortical malformations (89%), and ventriculomegaly (92%). Results from fetal brain volumetric assessment by magnetic resonance imaging showed that 1 of the most common findings associated with microcephaly was reduced supratentorial brain parenchyma and increased subarachnoid cerebrospinal fluid. Diffusion weighted imaging analyses of apparent diffusion coefficient values showed microstructural changes. Microcephaly was present in 33.3-58.3% of the cases at referral and was present at delivery in 55.6-77.8% of cases. At birth, most of the affected neonates (55.6-77.8%) had head circumference measurements >3 standard deviations below the mean. Postnatal imaging studies confirmed brain malformations that were detected prenatally. Auditory screening results were normal in 2 cases that were assessed. Visual screening showed different anomalies in 2 of the 3 cases that were examined. Pathologic results that were obtained from 2 of the 3 cases who opted for termination showed similar signs of abnormalities in the central nervous system and placental analyses, including brain microcalcifications. Congenital microcephaly is not an optimal screening method for congenital Zika virus syndrome, because it may not accompany other evident and preceding brain findings; microcephaly could be an endpoint of the disease that results from progressive changes that are related to brain volume loss. Long-term studies are needed to understand the clinical and developmental relevance of these findings.