Fetal and neonatal abnormalities due to congenital rubella syndrome: a review of literature

Fundus imaging features of congenital rubella retinopathy

PURPOSE

To evaluate the clinical characteristics of congenital rubella retinopathy (CRR) with modern fundus imaging.

METHODS

Single-center case series. Eleven patients (2005-2020) at the Emory Eye Center with known or presumed CRR. Trained image readers reviewed fundus imaging (color fundus photography, widefield pseudocolor imaging, near-infrared reflectance imaging, autofluorescence imaging, and spectral-domain optical coherence tomography) for pre-specified features suggestive of CRR.

RESULTS

Eleven patients with confirmed (63.6%) or presumed (36.3%) CRR were identified. All were female with median (range) age of 53 (35-67) years. Six (54.5%) were born during the 1964-1965 United States rubella epidemic. All had congenital hearing loss. Two (18.2%) had a congenital heart defect. Eleven (50.0%) eyes had salt-and-pepper retinal pigmentary changes. Twenty-two eyes (100.0%) had irregularly distributed regions of speckled hypoautofluorescence. One eye (4.5%) had a presumed macular neovascularization.

CONCLUSION

Modern fundus imaging demonstrates characteristic features of CRR, even when pigmentary changes are not readily apparent on examination. Widefield autofluorescence findings of irregularly distributed speckled hypoautofluorescence are particularly revealing. This series of newly diagnosed adults with CRR may represent the milder end of the phenotypic spectrum of this condition, highlighting imaging findings that may aid in diagnostically challenging cases of CRR.

Viral etiology of measles-like rash in Guinean children during the COVID epidemic in 2022

Covid-19 in West Africa masked outbreaks of vaccine-preventable diseases such as the measles epidemic in children in Guinea in 2021-2022 characterized by a lack of confirmation of suspected clinical cases. During weeks 13-22 of 2022, saliva samples were collected from 213 children (3-60 months old) with measles-like symptoms within the St Gabriel dispensary in Conakry. Samples were processed in Virus Transport Medium (VTM) and tested on the same day by triplex reverse transcriptase -real-time polymerase chain reaction for Measles, Rubella and RNaseP. Samples were also tested for HHV6 and Parvovirus B19, viruses causing clinical signs similar to measles. We confirmed 146 (68.5%) measles cases, 27 (12.7%) rubella, 5 (2.3%) double-positive measles-rubella, 35 (16.4%) HHV-6 and 8 (3.75%) Parvovirus B19. To test the assay's robustness, 27 samples were kept at 26-30°C. Measles and rubella were still detected after 7 days at 26-30°C, and after 21 days measles and rubella were still detectable in all samples but one. Sequencing indicated the circulation of the B3 measles genotype, as expected in West Africa. This study highlights the robustness of the measles/rubella diagnostic test on saliva samples stored in VTM. The high level of rubella detection questioned the single valence measles vaccination strategy.

Genetic Counseling of Fetal Microcephaly

Fetal microcephaly is a small head with various losses of cerebral cortical volume. The affected cases may suffer from a wide range in severity of impaired cerebral development from slight to severe mental retardation. It can be an isolated finding or with other anomalies depending on the heterogeneous causes including genetic mutations, chromosomal abnormalities, congenital infectious diseases, maternal alcohol consumption, and metabolic disorders during pregnancy. It is often a lifelong and incurable condition. Thus, early detection of fetal microcephaly and identification of the underlying causes are important for clinical staff to provide appropriate genetic counseling to the parents and accurate management.

A Study Prevalence of Congenital Rubella Syndrome Cases Before and After Rubella Vaccination Campaign

Rubella is a vaccine-preventable disease and is the leading cause of congenital disabilities. This study was performed to identify the congenital rubella syndrome (CRS) patients before and after the Rubella Vaccination Campaign in the Outpatient Unit of the Audiology Department at Dr. Soetomo General Hospital Surabaya. This was a descriptive study that used secondary data from a CRS surveillance case investigation form and medical records from 2015 to 2020 at Dr. Soetomo Hospital. A total of 346 suspected CRS cases were included in this study. According to the final classification, 145 (41.9%) patients had clinical CRS, 65 (18.8%) had confirmed CRS, and 136 (39.3%) had discarded CRS. The majority of the suspected cases were in the < 1-month age group (27.4%). Hearing loss was the most prevalent symptom in both the pre and post-rubella vaccination campaign (RVC) introduction periods campaign among groups. A patient with suspected CRS clinical signs.

Inherited causes of combined vision and hearing loss: clinical features and molecular genetics

Combined vision and hearing loss, also known as dual sensory impairment, can occur in several genetic conditions, including ciliopathies such as Usher and Bardet-Biedl syndrome, mitochondrial DNA disorders and systemic diseases, such as CHARGE, Stickler, Waardenburg, Alport and Alstrom syndrome. The retinal phenotype may point to the diagnosis of such disorders. Herein, we aim to provide a comprehensive review of the molecular genetics and clinical features of the most common non-chromosomal inherited disorders to cause dual sensory impairment.

Profile of cardiac lesions among laboratory confirmed congenital rubella syndrome (CRS) infants: a nationwide sentinel surveillance, India, 2016-22

Background

The phenotypical profile of cardiovascular malformations in patients with congenital rubella syndrome (CRS) is varied. We aimed to describe the profile of cardiac defects among CRS patients detected in the sentinel CRS surveillance in India during 2016-22.

Methods

Sentinel sites enrolled infants with suspected CRS based on presence of cardiac defects, hearing impairment, eye signs, or maternal history of febrile rash illness. Suspected CRS cases underwent detailed systemic examination, including echocardiography and serological investigation for rubella. Cardiac defects were categorized as 'Simple' or 'Complex' as per the National Heart, Lung, and Blood Institute classification. We compared the distribution of cardiac defects among laboratory confirmed CRS cases and seronegative discarded cases.

Findings

Of the 4578 suspected CRS cases enrolled by 14 sites, 558 (12.2%) were laboratory confirmed. 419 (75.1%) laboratory confirmed cases had structural heart defects (simple defects: n = 273, 65.2%, complex defects: n = 144, 34.4%), with ventricular septal defect (42.7%), atrial septal defect (39.4%), patent ductus arteriosus (36.5%), and tetralogy of Fallot as the commonest defects (4.5%). Laboratory confirmed CRS cases had higher odds of left to right shunt lesions (OR = 1.58, 95% CI: 1.15-2.17). This was mainly on account of a significant association of PDA with CRS (OR = 1.77, 95% CI: 1.42-2.21). Mortality was higher among CRS patients with complex heart defects (HR = 2.04, 95% CI: 1.26-3.30).

Interpretation

Three-fourths of the laboratory confirmed CRS cases had structural heart defects. CRS patients with complex cardiac defects had higher mortality. Detecting CRS infection early and providing timely intervention for cardiovascular defects is critical for the management of CRS patients.

Funding

Ministry of Health and Family Welfare, Govt of India, through Gavi, the Vaccine Alliance.

Considerable doubt about rubella screening and vaccination among unvaccinated orthodox protestant women: a mixed-methods study

BACKGROUND

Women who are susceptible to rubella are advised to vaccinate against rubella to prevent infection in future pregnancies, and thus avert the risk of congenital rubella syndrome in their unborn child. Rubella outbreaks periodically occur in the under-vaccinated orthodox Protestant community in the Netherlands. The objective of this mixed-methods study was to determine and understand personal experience with rubella, perceived rubella susceptibility, and intention to accept rubella screening and vaccination among unvaccinated orthodox Protestant women. The ultimate aim of this study was to inform policy and practice and contribute to the prevention of cases of congenital rubella syndrome.

METHODS

A mixed-methods study was conducted combining an online survey and semi-structured interviews among unvaccinated Dutch orthodox Protestant women aged 18-40 years. Descriptive analysis was used for quantitative data. Qualitative data was analysed using codes and categories.

RESULTS

Results of the survey (167 participants) showed that most participants had personal experience with rubella (74%, 123/167) and 101 women (61%, 101/167) indicated they had had rubella themselves. More than half of the women were undecided whether to accept rubella susceptibility screening (56%; 87/156) or rubella vaccination (55%; 80/146). Qualitative findings (10 participants) showed that most women thought they were not susceptible to rubella. Indecisiveness and negative attitudes to accept rubella vaccination were related with religious arguments to object vaccination and with women's perception of absence of imminent threat of rubella. Furthermore, results showed presence of misconceptions among women in the interpretation of their susceptibility and high confidence in their parents' memory that they had experienced rubella as a child although no laboratory screening had been conducted.

CONCLUSIONS

In light of an imminent rubella outbreak in the Netherlands, a tailored education campaign should be prepared aimed at and established in cooperation with the under-vaccinated orthodox Protestant community. Health care providers should provide adequate information on rubella and support decision-making in order to stimulate women to make a deliberate and informed decision on rubella screening and, if necessary, subsequent vaccination.

Impact of maternal hepatitis B carrier status on congenital abnormalities: a systematic review and meta-analysis

OBJECTIVES

This study aims to explore whether maternal hepatitis B carrier status is associated with an increased risk of congenital abnormalities.

DESIGN

A systematic review and meta-analysis of observational studies.

DATA SOURCES

PubMed, Embase (Ovid), Scopus, the China National Knowledge Infrastructure (CNKI) and the Wanfang databases.

STUDY SELECTION

Five databases were searched systematically from inception to 7 September 2021. Cohort and case-control studies that investigated the association between maternal hepatitis B virus (HBV) infection and congenital abnormalities were included. This study was conducted according to MOOSE (Meta-analysis of Observational Studies in Epidemiology) guidelines.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently collected data, as well as assessed risk of bias by using Newcastle-Ottawa Scale. We pooled crude relative risk (cRR) and adjusted OR (aOR) by DerSimonian-Laird random-effects model. Heterogeneity was explored by I ² statistics, Cochran's Q test. Several subgroup analyses and sensitivity analyses were performed.

RESULTS

In total, 14 studies involving 16 205 pregnant women exposed to HBV were included. The pooled cRR of 1.15 (95% CI: 0.92 to 1.45; 14 studies included) showed a marginal but not significant association between maternal HBV-carrier status and congenital abnormalities. However, the pooled aOR of 1.40 (95% CI: 1.01 to 1.93; 8 studies included) indicated that pregnant women with HBV infection might be associated with a higher risk of congenital abnormalities. Subgroup analyses of adjusted data showed a higher pooling cRR or aOR on high prevalence HBV infection populations, as well as studies from Asia and Oceania.

CONCLUSIONS

Maternal hepatitis B carrier status might be at potential risk for congenital abnormalities. The existing evidence was not sufficient to draw a firm conclusion. Additional studies may be warranted to confirm the association.

PROSPERO REGISTRATION NUMBER

CRD42020205459.

Intrauterine and Perinatal Infections

Imaging plays an important role in evaluating patients with suspected intrauterine and perinatal infections. Advances in fetal imaging including both ultrasound and MRI allow for increasingly more specific diagnosis if the radiologist is familiar with specific imaging features and patterns. Early imaging of neonates with suspected central nervous system infection is valuable to enable prompt treatment and differentiate infection from other conditions which can clinically present similarly. Ultrasound is a useful initial modality to screen for abnormalities however MRI with and without contrast remains the optimal examination to characterize infection, evaluate for potential surgical targets, and provide prognostic information.

Covid-19 vaccination in pregnancy

Pregnancy is an independent risk factor for severe covid-19. Vaccination is the best way to reduce the risk for SARS-CoV-2 infection and limit its morbidity and mortality. The current recommendations from the World Health Organization, Centers for Disease Control and Prevention, and professional organizations are for pregnant, postpartum, and lactating women to receive covid-19 vaccination. Pregnancy specific considerations involve potential effects of vaccination on fetal development, placental transfer of antibodies, and safety of maternal vaccination. Although pregnancy was an exclusion criterion in initial clinical trials of covid-19 vaccines, observational data have been rapidly accumulating and thus far confirm that the benefits of vaccination outweigh the potential risks. This review examines the evidence supporting the effectiveness, immunogenicity, placental transfer, side effects, and perinatal outcomes of maternal covid-19 vaccination. Additionally, it describes factors associated with vaccine hesitancy in pregnancy. Overall, studies monitoring people who have received covid-19 vaccines during pregnancy have not identified any pregnancy specific safety concerns. Additional information on non-mRNA vaccines, vaccination early in pregnancy, and longer term outcomes in infants are needed. To collect this information, vaccination during pregnancy must be prioritized in vaccine research.

Ultrasound Findings of Fetal Infections: Current Knowledge

Infectious diseases during pregnancy are still a major cause of fetal mortality and morbidity worldwide. The most common teratogenic pathogens are cytomegalovirus (CMV), varicella-zoster virus (VZV), rubeovirus, parvovirus B19, herpes simplex virus (HSV), Toxoplasma gondii, Treponema pallidum and the emergent Zika virus (ZIKV). Ultrasound findings include cerebral anomalies, orbital defects, micrognathia, cardiac defects, hepatosplenomegaly, liver calcifications, abdominal anomalies, skin and limb anomalies, edema, placental and amniotic fluid anomalies and altered Doppler analyses. The classification of ultrasound markers of congenital infections by anatomical region is reported to guide differential diagnosis and prenatal care.

Low Susceptibility of Rubella Virus in First-Trimester Trophoblast Cell Lines

We recently published an article about myelin oligodendrocyte glycoprotein-independent rubella infection of keratinocytes in vitro, in which first-trimester trophoblast cells were shown as rubella virus (RuV)-resistant. Given an incident rate as high as 90% of congenital rubella syndrome in the first eight weeks of pregnancy, the RuV infection of first-trimester trophoblasts is considered key to opening the gate to transplacental transmission mechanisms. Therefore, with this study, we aimed to verify the susceptibility/resistance of first-trimester trophoblast cell lines, HTR-8/SVneo and Swan.71, against RuV. Cells cultured on multi-well plates were challenged with a RuV clinical strain at a multiplicity of infection from 5 to 10 for 3 h. The infectivity was investigated by immunofluorescence (IF) assay and flow cytometry (FCM) analysis. Supernatants collected during the post-infection period were used to determine virus-progeny production. The scattered signaling of RuV infection of these cells was noted by IF assay, and the FCM analysis showed an average of 4-5% of gated cells infected with RuV. In addition, a small but significant production of virus progeny was also observed. In conclusion, by employing appropriate approaches, we determined the low infectivity of RuV in first-trimester trophoblast cell lines but not resistance as in our previous report.

Susceptibility to Rubella Infection and Incidence of Congenital Rubella Infection: 6 Years Retrospective Study

Introduction

Rubella is considered one of the most serious and most common congenital infections. Despite global efforts for elimination, rubella cases are still being reported in many parts of the world. The purpose of this study is to determine the level of immunity to rubella in the community and most importantly among women at childbearing age in the eastern province of Saudi Arabia and compare it with the target set by the World Health Organization (WHO) along with the incidence of acute rubella infection and the associated congenital rubella infection and congenital rubella syndrome.

Methods

This is a retrospective cross-sectional study over the six years period (Jan 2014–Jun 2020) on all individuals tested for rubella IgM and IgG in a university teaching hospital.

Results

Nighty one percent (15,894/17,469) of the population tested showed evidence of rubella immunity with 8.8% (1546/17,469) being susceptible. Among women at childbearing age, susceptibility to rubella was higher with 9.2% (1220/13,278) of women showing no evidence of immunity. In addition, acute rubella infection was reported for 0.17% (29/17,469) of the population tested and 0.15% (20/13,278) in women at childbearing age. No cases of congenital rubella infection were reported in the study period.

Discussion

The level of Rubella immunity in the population is 91% and is less than the WHO target for rubella control therefore, risk of resurge of cases is present, indicating the need for continued national surveillance and more efforts to improve vaccination coverage in the kingdom.

Rubella virus-associated uveitis: The essentiality of aqueous humor virological analysis

AIMS / BACKGROUND

Rubella virus-associated uveitis (RVAU) classically presents with the clinical features of Fuchs uveitis syndrome (FUS). We report a series RVAU, and discuss the relevance of available diagnostic strategies, and how vaccination could potentially prevent disease.

METHODS

We retrospectively included patients with RV-positive aqueous humor (AH) with RT-PCR and/or intraocular RV-IgG production, between January 2014 and December 2019. RV-IgG titers from AH and serum were compared with other virus-specific IgG titers (VZV and/or CMV and/or HSV-1), to determine the derived Goldmann-Witmer coefficient (GWC'). Clinical findings at presentation and during follow-up are reported, as well as the anti-RV vaccination status.

RESULTS

All 13 included patients demonstrated intraocular synthesis of RV-IgG (median GWC': 9.5; 3.2-100). RV-RNA was detected in one patient while PCR results were negative for other HSV1, VZV and CMV. The mean delay in diagnosis was 13 ± 12.6 years, with an initial presentation of FUS in only 3 patients (23%). Only four patients had been vaccinated, but all after the recommended age.

CONCLUSION

As RVAU is a pleiomorphic entity, virological analysis (RV RT-PCR and GWC') of aqueous humor is essential to improve the diagnosis and management of this entity. Improper vaccination against RV appears to be implicated in RVAU.

Congenital Heart Disease: An Immunological Perspective

Congenital heart disease (CHD) poses a significant global health and economic burden-despite advances in treating CHD reducing the mortality risk, globally CHD accounts for approximately 300,000 deaths yearly. Children with CHD experience both acute and chronic cardiac complications, and though treatment options have improved, some remain extremely invasive. A challenge in addressing these morbidity and mortality risks is that little is known regarding the cause of many CHDs and current evidence suggests a multifactorial etiology. Some studies implicate an immune contribution to CHD development; however, the role of the immune system is not well-understood. Defining the role of the immune and inflammatory responses in CHD therefore holds promise in elucidating mechanisms underlying these disorders and improving upon current diagnostic and treatment options. In this review, we address the current knowledge coinciding CHDs with immune and inflammatory associations, emphasizing conditions where this understanding would provide clinical benefit, and challenges in studying these mechanisms.

Intrauterine exposure to Zika virus and hearing loss within the first few years of life: A systematic literature review

BACKGROUND

Identification of the factors that could potentially lead to congenital hearing loss is of paramount importance, as early detection of congenital hearing loss and intervention could prevent developmental delays in speech, language development as well as childhood cognitive impairment. Hitherto, intrauterine exposure to Zika virus has emerged as a cause of various fetal malformations, including cases of congenital hearing loss. The aim of this systematic review is to investigate the association between intrauterine exposure to Zika virus and hearing loss in children.

METHODS

A systematic literature search was conducted to the databases PubMed, Cochrane library, Scopus, ClinicalTrials.gov, SciELO and Lilacs in order to identify studies that examine the association between prenatally Zika exposure and hearing loss within the first few years of life. Studies were eligible for inclusion, if solely objective methods for hearing evaluation of patients such as otoacoustic emissions (OAEs) and/or auditory brainstem response (ABR) were used, in children who intrauterine exposed to the Zika virus.

RESULTS

Thirteen studies were included, which included 1275 children who are prenatally exposed to Zika virus. In 852 of the cases an objective hearing evaluation was performed using either OAEs or ABR. 709 children were tested with ABR and 79 had a failed outcome. 143 children were tested with OAEs whilst of these, 30 had a failed outcome. Altered OAEs ranged from 8.7% to 30.2%, while altered ABR ranged from 0% to 19.9%. The initial sample includes 428 children with microcephaly, while 5 of the studies comprise microcephaly to the inclusion criteria.

CONCLUSION

It seems to be a possible association between prenatal Zika virus exposure and hearing loss in children during the first years of their life. It is of great importance that in future studies possible confounding factors, like microcephaly, will be appropriately controlled. Additionally, the follow-up period of monitoring hearing loss in children should be prolonged in order to identify potential late onset hearing problems caused by intrauterine exposure to Zika virus.

Pregnancy and viral infections: Mechanisms of fetal damage, diagnosis and prevention of neonatal adverse outcomes from cytomegalovirus to SARS-CoV-2 and Zika virus

Some maternal infections, contracted before or during pregnancy, can be transmitted to the fetus, during gestation (congenital infection), during labor and childbirth (perinatal infection) and through breastfeeding (postnatal infection). The agents responsible for these infections can be viruses, bacteria, protozoa, fungi. Among the viruses most frequently responsible for congenital infections are Cytomegalovirus (CMV), Herpes simplex 1–2, Herpes virus 6, Varicella zoster. Moreover Hepatitis B and C virus, HIV, Parvovirus B19 and non-polio Enteroviruses when contracted during pregnancy may involve the fetus or newborn at birth. Recently, new viruses have emerged, SARS-Cov-2 and Zika virus, of which we do not yet fully know the characteristics and pathogenic power when contracted during pregnancy.

Viral infections in pregnancy can damage the fetus (spontaneous abortion, fetal death, intrauterine growth retardation) or the newborn (congenital anomalies, organ diseases with sequelae of different severity). Some risk factors specifically influence the incidence of transmission to the fetus: the timing of the infection in pregnancy, the order of the infection, primary or reinfection or chronic, the duration of membrane rupture, type of delivery, socio-economic conditions and breastfeeding. Frequently infected neonates, symptomatic at birth, have worse outcomes than asymptomatic. Many asymptomatic babies develop long term neurosensory outcomes.

The way in which the virus interacts with the maternal immune system, the maternal-fetal interface and the placenta explain these results and also the differences that are observed from time to time in the fetal‑neonatal outcomes of maternal infections. The maternal immune system undergoes functional adaptation during pregnancy, once thought as physiological immunosuppression. This adaptation, crucial for generating a balance between maternal immunity and fetus, is necessary to promote and support the pregnancy itself and the growth of the fetus. When this adaptation is upset by the viral infection, the balance is broken, and the infection can spread and lead to the adverse outcomes previously described. In this review we will describe the main viral harmful infections in pregnancy and the potential mechanisms of the damages on the fetus and newborn.

Case series of 20 pregnant women with 2019 novel coronavirus disease in Wuhan, China

AIM

To evaluate perinatal outcomes regarding clinical presentation in pregnancy and the vertical transmission potential of COVID-19.

METHODS

Clinical records, laboratory findings, and chest computed tomography (CT) scans were retrospectively reviewed from 20 pregnant patients with laboratory-confirmed COVID-19 who were admitted to Renmin Hospital of Wuhan University and The Third Hospital of Wuhan, from Jan 20 to Mar 16, 2020, including three in the first-trimester, two in the second-trimester, and 15 in the third-trimester. Evidence of vertical transmission was assessed by testing for neonatal throat swab samples. The pathological changes of COVID-19 on the placenta is evaluated by hematoxylin-eosin staining.

RESULTS

The most common symptoms of the pregnant women with SARS-CoV-2 infection were fever and cough, which is comparable to the nonpregnant adults with COVID-19 infection. Nobody was transferred to intensive care unit (ICU) for treatment and there were no maternal and neonatal deaths. However, there was one case with induced abortions on first-trimester (due to pregnant woman's concerns about COVID-19), one diagnosed with ectopic pregnancy, no intrauterine fetal deaths during the study period. Delivery occurred in 15 patients in the third trimester. Their incidence of preterm birth was 20%. Three of the four preterm births were spontaneous. The average length of stay was 20.77 days. No neonatal SARS-CoV-2 infection was detected. There were two placentas found with acute chorioamnionitis, one showed normal placenta morphology.

CONCLUSION

In this case series study, COVID-19 had no short-term adverse effect on pregnant women except premature birth. The vertical transmission of SARS-CoV-2 did not occur in our study.

EPHA2 Segregates with Microphthalmia and Congenital Cataracts in Two Unrelated Families

EPHA2 is a transmembrane tyrosine kinase receptor that, when disrupted, causes congenital and age-related cataracts. Cat-Map reports 22 pathogenic EPHA2 variants associated with congenital cataracts, variable microcornea, and lenticonus, but no previous association with microphthalmia (small, underdeveloped eye, ≥2 standard deviations below normal axial length). Microphthalmia arises from ocular maldevelopment with >90 monogenic causes, and can include a complex ocular phenotype. In this paper, we report two pathogenic EPHA2 variants in unrelated families presenting with bilateral microphthalmia and congenital cataracts. Whole genome sequencing through the 100,000 Genomes Project and cataract-related targeted gene panel testing identified autosomal dominant heterozygous mutations segregating with the disease: (i) missense c.1751C>T, p.(Pro584Leu) and (ii) splice site c.2826-9G>A. To functionally validate pathogenicity, morpholino knockdown of epha2a/epha2b in zebrafish resulted in significantly reduced eye size ± cataract formation. Misexpression of N-cadherin and retained fibre cell nuclei were observed in the developing lens of the epha2b knockdown morphant fish by 3 days post-fertilisation, which indicated a putative mechanism for microphthalmia pathogenesis through disruption of cadherin-mediated adherens junctions, preventing lens maturation and the critical signals stimulating eye growth. This study demonstrates a novel association of EPHA2 with microphthalmia, suggesting further analysis of pathogenic variants in unsolved microphthalmia cohorts may increase molecular diagnostic rates.

Immune Regulation, Maternal Infection, Vaccination, and Pregnancy Outcome

About 12.5% of all maternal deaths in the United States are due to infectious causes. This proportion, although stable during the past three decades, represents an increase in infectious causes of mortality, as the overall mortality rate in U.S. pregnant women had increased steadily during that same period. During healthy pregnancies, a delicate immunological balance-in which a mother's immune system tolerates the semi-allogeneic fetus yet maintains immune competency against infectious agents-is achieved and maintained. This immunological paradigm, however, results in increased susceptibility to infectious diseases during pregnancy, particularly in later stages and during the early postpartum period. The inflammatory process induced by these infectious insults, as well as some noninfectious insults, occurring during pregnancy can disrupt this carefully achieved balance and, in turn, lead to a state of rampant inflammation, immune activation, and dysregulation with deleterious health outcomes for the mother and fetus. Elucidating mechanisms contributing to the disruption of this immunologic homeostasis, and its disruption by infectious pathogens, might offer opportunities for interventions to reduce maternal and fetal morbidity and mortality.

Coxsackievirus B3 Infection Early in Pregnancy Induces Congenital Heart Defects Through Suppression of Fetal Cardiomyocyte Proliferation

Background Coxsackievirus B (CVB) is the most common cause of viral myocarditis. It targets cardiomyocytes through coxsackie and adenovirus receptor, which is highly expressed in the fetal heart. We hypothesized CVB3 can precipitate congenital heart defects when fetal infection occurs during critical window of gestation. Methods and Results We infected C57Bl/6 pregnant mice with CVB3 during time points in early gestation (embryonic day [E] 5, E7, E9, and E11). We used different viral titers to examine possible dose-response relationship and assessed viral loads in various fetal organs. Provided viral exposure occurred between E7 and E9, we observed characteristic features of ventricular septal defect (33.6%), abnormal myocardial architecture resembling noncompaction (23.5%), and double-outlet right ventricle (4.4%) among 209 viable fetuses examined. We observed a direct relationship between viral titers and severity of congenital heart defects, with apparent predominance among female fetuses. Infected dams remained healthy; we did not observe any maternal heart or placental injury suggestive of direct viral effects on developing heart as likely cause of congenital heart defects. We examined signaling pathways in CVB3-exposed hearts using RNA sequencing, Kyoto Encyclopedia of Genes and Genomes enrichment analysis, and immunohistochemistry. Signaling proteins of the Hippo, tight junction, transforming growth factor-β1, and extracellular matrix proteins were the most highly enriched in CVB3-infected fetuses with ventricular septal defects. Moreover, cardiomyocyte proliferation was 50% lower in fetuses with ventricular septal defects compared with uninfected controls. Conclusions We conclude prenatal CVB3 infection induces congenital heart defects. Alterations in myocardial proliferate capacity and consequent changes in cardiac architecture and trabeculation appear to account for most of observed phenotypes.

Chorioamnionitis in utero, schizophrenia in adulthood: limited current evidence-future research focus?

Background: Developmental adaptive processes during gestation that are known to be involved in permanent changes in physiology and metabolism or "early life programming" can adversely affect fetal brain development, impacting both brain structure and function.Data: Emerging evidence strongly supports the developmental origin of schizophrenia, which may potentially be a result of prenatal exposure to a diversity of factors, especially infections, in genetically predisposed subjects. Structural and functional brain changes during development of schizophrenia are determined by genetic components, altered expression of schizophrenia risk genes and epigenetic dysregulation. However, the precise mechanisms underlying these relationships remain unclear. Findings from human and animal studies suggest that inflammatory-immune responses and activation of oxidative stress pathways are crucial in mediating intrauterine infection-induced neurodevelopmental and neuropsychiatric diseases.Aim: Considering the high prevalence of intrauterine inflammation in the context of chorioamnionitis during human pregnancy and the paucity of knowledge on fetal programming of schizophrenia, this mini review aims to exclusively consolidate the current evidence supporting a potential association between chorioamnionitis and schizophrenia.

Study of the teratogenicity of the vaccine strain of the Rubella virus «Orlov-V» (Matonaviridae: Rubivirus: Rubella virus) in experience on rhesus macaques

INTRODUCTION

Rubella virus has pronounced teratogenic properties that can cause generalized and persistent intrauterine infection of the fetus. As a result, the control of the loss of teratogenicity inherent in «wild-type» virus strains is a necessary stage of a preclinical study of the vaccine strain for a live attenuated rubella vaccine.The purpose of the study is to comprehensively study the teratogenic properties of the vaccine strain of rubella virus «Orlov-V» in the experiment on rhesus macaques.

MATERIAL AND METHODS

Seronegative to rubella virus female rhesus macaques in early pregnancy at the age of 4-7 years (n = 13) were used in the experiment. Animals of the experimental group (n = 9) received single immunization intramuscularly with a preparation from the «Orlov-V» strain. The control group of the monkeys (n = 3) were immunized with a commercial vaccine containing Wistar RA27/3 strain. The female of the control group (n = 1) was injected with a solvent used in the rubella vaccine. Study of possible teratogenic properties of vaccine strains of rubella virus was carried out using a complex of clinical, immunological, pathomorphological and virological methods. Clinical observations were made within 3 months after the monkeys' birth. Determination of antibody titers in the blood serum of immunized monkeys was performed in HI test on the 28th-30th day after infection. The ELISA method was applied to determine IgM antibodies in the blood serum of newborns within the first month of life. Detection of rubella virus RNA was performed by PCR with electrophoretic detection of amplicons.

RESULTS

No markers of congenital rubella infection were found in infants born from monkeys vaccinated during the pregnancy. It is shown that PCR can be an informative method to confirm the absence of teratogenic properties of vaccine strains of rubella virus.

DISCUSSION

The obtained data demonstrated that vaccine strains of the «Orlov-V» rubella virus and Wistar RA27/3 have lost their teratogenic properties. The possibility of using an alternative strategy for preclinical assessment of specific safety of antiviral vaccines including a complex of clinical, immunological, pathologic and virological methods instead of the classical pathologic method is discussed.

CONCLUSION

The results obtained in this study showed the absence of teratogenic properties and high immunogenic activity of the vaccine strain of rubella virus «Orlov-V».

Vaccines for Perinatal and Congenital Infections-How Close Are We?

Congenital and perinatal infections are transmitted from mother to infant during pregnancy across the placenta or during delivery. These infections not only cause pregnancy complications and still birth, but also result in an array of pediatric morbidities caused by physical deformities, neurodevelopmental delays, and impaired vision, mobility and hearing. Due to the burden of these conditions, congenital and perinatal infections may result in lifelong disability and profoundly impact an individual's ability to live to their fullest capacity. While there are vaccines to prevent congenital and perinatal rubella, varicella, and hepatitis B infections, many more are currently in development at various stages of progress. The spectrum of our efforts to understand and address these infections includes observational studies of natural history of disease, epidemiological evaluation of risk factors, immunogen design, preclinical research of protective immunity in animal models, and evaluation of promising candidates in vaccine trials. In this review we summarize this progress in vaccine development research for Cytomegalovirus, Group B Streptococcus, Herpes simplex virus, Human Immunodeficiency Virus, Toxoplasma, Syphilis, and Zika virus congenital and perinatal infections. We then synthesize this evidence to examine how close we are to developing a vaccine for these infections, and highlight areas where research is still needed.

Knowledge regarding teratogens among women of childbearing age at a large tertiary care center in Saudi Arabia

AIM

To investigate the knowledge of Saudi women regarding the teratogenic effects of environmental agents such as fever, some chronic conditions and medications and its association with certain socio-demographic factors.

MATERIALS AND METHODS

A survey based cross-sectional study was conducted on 315 Saudi women of childbearing age visiting OB/GYN clinics at a large tertiary care centre in Riyadh, Saudi Arabia. Knowledge of subjects on teratogenic risk of common entities was measured and nonparametric Mann-Whitney and Kruskal-Wallis tests were used to associate knowledge score with various predictors.

RESULTS

The response rate was 75%. Most of the participants were between 28 and 37 years. Knowledge on teratogenic risk was generally poor with specifically higher knowledge regarding insulin intake and isotretinoin. Older age, higher education, being employed, and having a high monthly income were significantly associated with a higher knowledge score (P < 0.05).

CONCLUSION

Women's knowledge regarding teratogenic risks is crucial in ensuring a safe pregnancy and a healthy fetus. Our study revealed inadequate knowledge of teratogens among the participants which implies an urgent need to increase awareness of mothers regarding the harmful effects of common teratogens.

Congenital heart diseases: genetics, non-inherited risk factors, and signaling pathways

Background

Congenital heart diseases (CHDs) are the most common congenital anomalies with an estimated prevalence of 8 in 1000 live births. CHDs occur as a result of abnormal embryogenesis of the heart. Congenital heart diseases are associated with significant mortality and morbidity. The damage of the heart is irreversible due to a lack of regeneration potential, and usually, the patients may require surgical intervention. Studying the developmental biology of the heart is essential not only in understanding the mechanisms and pathogenesis of congenital heart diseases but also in providing us with insight towards developing new preventive and treatment methods.

Main body

The etiology of congenital heart diseases is still elusive. Both genetic and environmental factors have been implicated to play a role in the pathogenesis of the diseases. Recently, cardiac transcription factors, cardiac-specific genes, and signaling pathways, which are responsible for early cardiac morphogenesis have been extensively studied in both human and animal experiments but leave much to be desired. The discovery of novel genetic methods such as next generation sequencing and chromosomal microarrays have led to further study the genes, non-coding RNAs and subtle chromosomal changes, elucidating their implications to the etiology of congenital heart diseases. Studies have also implicated non-hereditary risk factors such as rubella infection, teratogens, maternal age, diabetes mellitus, and abnormal hemodynamics in causing CHDs.

These etiological factors raise questions on multifactorial etiology of CHDs. It is therefore important to endeavor in research based on finding the causes of CHDs. Finding causative factors will enable us to plan intervention strategies and mitigate the consequences associated with CHDs. This review, therefore, puts forward the genetic and non-genetic causes of congenital heart diseases. Besides, it discusses crucial signaling pathways which are involved in early cardiac morphogenesis. Consequently, we aim to consolidate our knowledge on multifactorial causes of CHDs so as to pave a way for further research regarding CHDs.

Conclusion

The multifactorial etiology of congenital heart diseases gives us a challenge to explicitly establishing specific causative factors and therefore plan intervention strategies. More well-designed studies and the use of novel genetic technologies could be the way through the discovery of etiological factors implicated in the pathogenesis of congenital heart diseases.

Maternal infections

Congenital infections are infections transmitted from mother to child during pregnancy (transplacentally) or delivery (peripartum). They have the potential to adversely affect fetal development and long-term neurodevelopmental outcome through inflammatory, destructive, developmental, or teratogenic lesions of the brain. Because the fetal/neonatal brain has a limited capacity to respond to injury, early inflammatory changes may be difficult to visualize and only manifest as neurocognitive disability later in life. Teratogenic effects, which may include aberrations of neuronal proliferation and migration, are more easily visible on imaging, but may be equally difficult to use to predict long-term neurocognitive outcomes. This chapter reviews the general pathophysiology of congenital infection and describes the epidemiology, the antenatal and postnatal diagnosis, and the treatment of congenital infections as well as the long-term neurodevelopmental outcomes.

Key Infections in the Placenta

Congenital infections are an important cause of morbidity and mortality worldwide, especially in low-income settings. This review discusses the main pathways of infections and associated adverse maternal and fetal outcomes, considering the TORCH pathogens, including Zika virus; the acronym stands for Toxoplasma gondii infection, other (Listeria monocytogenes, Treponema pallidum, and parvovirus B19, among others, including Zika virus), rubella virus, cytomegalovirus, and herpes simplex viruses type 1 and type 2.

Risk factors associated with fetal pleural effusion in prenatal diagnosis: a retrospective study in a single institute in Southern China

The aim of this study was to analyse the factors associated with fetal pleural effusion over the past five years in a single institute in the South of China. Between January 2011 and May 2016, 129 foetuses with pleural effusion were referred to the Fetal Medicine Unit in Guangzhou's Women and Children's Medical Center. Seventy-nine women accepted an invasive procedure to rule out chromosomal abnormalities, fetal anaemia, intrauterine infections or some of the submicroscopic chromosomal abnormalities. Our results showed that chromosomal anomalies occurred in 15.2% (12/79) of cases including 8 Turner syndrome (45, X) (10.1%), 3 trisomy 21 (3.8%) and 1 trisomy 13 (1.3%). Pathological microdeletion or microduplication syndrome occurred in 3 out of 36 (8.3%) prenatal samples with normal karyotype and structural defects. Eight foetuses (10.1%) affected with haemoglobin Bart's disease showed pleural effusion at second or third trimester. Two cases (2.5%) were found to have an intrauterine infection. In conclusion, fetal pleural effusion has a close correlation with chromosomal abnormality. CMA may increase the detection rate of chromosomal aberrations, especially for micro-deletion or micro-duplication syndromes. In the South of China, Thalassemia must be considered when a fetal pleural effusion is detected.Impact statementWhat is already known on this subject? The aetiology of fetal pleural effusion includes a chromosomal abnormality, a congenital heart disease, congenital infections and a number of genetic syndromes.What do the results of this study add? This is the first retrospective study to analyse the aetiology of fetal pleural effusion in one institute in the South of China.What are the implications of these findings for clinical practice and/or further research? Besides the chromosomal abnormality, micro-deletion and micro-duplication syndromes were also detected in our study. We feel that thalassemia must be considered when fetal pleural effusion is detected in South China.

The fetal origins of mental illness

The impact of infections and inflammation during pregnancy on the developing fetal brain remains incompletely defined, with important clinical and research gaps. Although the classic infectious TORCH pathogens (ie, Toxoplasma gondii, rubella virus, cytomegalovirus [CMV], herpes simplex virus) are known to be directly teratogenic, emerging evidence suggests that these infections represent the most extreme end of a much larger spectrum of injury. We present the accumulating evidence that prenatal exposure to a wide variety of viral and bacterial infections-or simply inflammation-may subtly alter fetal brain development, leading to neuropsychiatric consequences for the child later in life. The link between influenza infections in pregnant women and an increased risk for development of schizophrenia in their children was first described more than 30 years ago. Since then, evidence suggests that a range of infections during pregnancy may also increase risk for autism spectrum disorder and depression in the child. Subsequent studies in animal models demonstrated that both pregnancy infections and inflammation can result in direct injury to neurons and neural progenitor cells or indirect injury through activation of microglia and astrocytes, which can trigger cytokine production and oxidative stress. Infectious exposures can also alter placental serotonin production, which can perturb neurotransmitter signaling in the developing brain. Clinically, detection of these subtle injuries to the fetal brain is difficult. As the neuropsychiatric impact of perinatal infections or inflammation may not be known for decades after birth, our construct for defining teratogenic infections in pregnancy (eg, TORCH) based on congenital anomalies is insufficient to capture the full adverse impact on the child. We discuss the clinical implications of this body of evidence and how we might place greater emphasis on prevention of prenatal infections. For example, increasing uptake of the seasonal influenza vaccine is a key strategy to reduce perinatal infections and the risk for fetal brain injury. An important research gap exists in understanding how antibiotic therapy during pregnancy affects the fetal inflammatory load and how to avoid inflammation-mediated injury to the fetal brain. In summary, we discuss the current evidence and mechanisms linking infections and inflammation with the increased lifelong risk of neuropsychiatric disorders in the child, and how we might improve prenatal care to protect the fetal brain.

No. 368-RUBELLA IN PREGNANCY

OBJECTIVE

To review the epidemiology, natural history, evaluation, and prevention of rubella infection during pregnancy. This will aid obstetric care providers in counseling their patients regarding potentially devastating effects on the developing fetus and the importance of vaccinating susceptible women as appropriate.

OUTCOMES

Outcomes evaluated include fetal rubella infection, maternal seroconversion and response to rubella-containing vaccines.

EVIDENCE

Medline, PubMed, EMBASE, and Cochrane databases were searched for articles in English on subjects related to rubella infection during pregnancy betweenn 1985 and 2017. Results were restricted to systematic reviews, randomized controlled trials/controlled clinical trials, and observational studies. Other (unpublished) literature was identified through searching the websites of health technology assessment and health technology assessment-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALUATION METHODS

The quality of the evidence is rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1). Recommendations for practice are ranked according to the method described in this Report.

GUIDELINE UPDATE

The guideline will be reviewed 5 years after publication to decide if an update is required. However, if important new evidence is published prior to the 5-year cycle, the review process may be accelerated for a more rapid update of some recommendations SPONSOR: Society of Obstetricians and Gynaecologists of Canada.

RECOMMENDATIONS

Zika Virus Infection and Microcephaly: A Case-Control Study in Brazil

BACKGROUND

Brazil presented an alarming number of newborns with microcephaly in the years 2015 and 2016. The investigation of the cases raised the suspicion of the association of these cases with maternal infections by the zika virus. Also, in 2015, there was an epidemic of zika virus infection in Brazil, reinforcing this hypothesis.

OBJECTIVE

The objective of this study was to identify factors associated with the diagnosis of microcephaly in newborns, including zika virus infection.

METHODS

We conducted a case-control study. The cases were defined as children who received clinical and imaging diagnosis of microcephaly, born after October 2015 in Ceará, Brazil, which recorded the highest number of microcephaly cases in Brazil during the outbreak. The cases were identified in medical records of public and private maternity hospitals and in child development stimulation clinics tracked until June 2017. Epidemiological, clinical, and socioeconomic variables were collected, visiting their homes and confirming data from their medical records. Controls were children without microcephaly identified in the vicinity of the residence of each case. Logistic regression models were used to control confounding.

FINDINGS

We evaluated 58 cases and 116 controls. The odds of having a baby with microcephaly was 14 times higher among mothers who had zika virus infection (p < 0.001), after multivariate analysis. Arboviruses infections symptoms, as fever (p = 0.220), skin change (p < 0.001), and joint pain (p = 0.002) also demonstrated an association with microcephaly.

CONCLUSIONS

Maternal infection zika virus was associated with a diagnosis of microcephaly. Our study contributes to the investigation of the epidemiological factors associated with the diagnosis of microcephaly.

Ultrasound Findings Associated With Antepartum Viral Infection

This article reviews the sonographic manifestations of fetal infection and the role of ultrasound in the evaluation of the fetus at risk for congenital infection. Several ultrasound findings have been associated with in utero fetal infections. For the patient with a known or suspected fetal infection, sonographic identification of characteristic abnormalities can provide useful information for counseling and perinatal management. Demonstration of such findings in the low-risk patient may serve to identify the fetus with a previously unsuspected infection. The clinician should understand the limitations of ultrasound in the prenatal diagnosis of congenital infection and discuss them with the patient.

Plasmonic gold chips for the diagnosis of Toxoplasma gondii, CMV, and rubella infections using saliva with serum detection precision

Sampling the blood compartment by an invasive procedure such as phlebotomy is the most common approach used for diagnostic purposes. However, phlebotomy has several drawbacks including pain, vasovagal reactions, and anxiety. Therefore, alternative approaches should be tested to minimize patient's discomfort. Saliva is a reasonable compartment; when obtained, it generates little or no anxiety. We setup a multiplexed serology assay for detection of Toxoplasma gondii IgG and IgM, rubella IgG, and CMV IgG, in serum, whole blood, and saliva using novel plasmonic gold (pGOLD) chips. pGOLD test results in serum, whole blood, and saliva were compared with commercial kits test results in serum. One hundred twenty serum/saliva sets (Lyon) and 28 serum/whole blood/saliva sets (Nice) from France were tested. In serum and whole blood, sensitivity and specificity of multiplex T. gondii, CMV, and rubella IgG were 100% in pGOLD when compared to commercial test results in serum. In saliva, sensitivity and specificity for T. gondii and rubella IgG were 100%, and for CMV IgG, sensitivity and specificity were 92.9% and 100%, respectively, when compared to commercial test results in serum. We were also able to detect T. gondii IgM in saliva with sensitivity and specificity of 100% and 95.4%, respectively, when compared to serum test results. Serological testing by multiplex pGOLD assay for T. gondii, rubella, and CMV in saliva is reliable and likely to be more acceptable for systematic screening of pregnant women, newborn, and immunocompromised patients.

Pulmonary Artery Obstruction by Idiopathic Calcification Causing Sudden Collapse in a Neonate

We report a case of a newborn infant who experienced circulatory collapse caused by a calcified lesion occluding the main pulmonary artery (PA). The baby was full-term at birth at a normal birth weight. Cyanosis was noted immediately after birth. Echocardiography revealed a main PA occlusion caused by a calcified lesion. Bradycardia and circulatory failure occurred at postnatal day 4, and an urgent surgical resection was successfully performed. Idiopathic calcification causing both PA obstruction and circulatory collapse is rare. Our report indicates that PA calcification can cause hemodynamic instability requiring early surgical intervention.

Epidemiology of rubella infection and genotyping of rubella virus in Cote d'Ivoire, 2012-2016

Rubella is a contagious disease caused by the rubella virus (RuV) that can lead to serious birth defects when women are infected in early pregnancy. This study aimed to describe the epidemiology and genetic diversity of rubella viruses in Cote d'Ivoire (CIV). Blood or oral fluid samples collected from suspected measles cases were first tested for the presence of measles specific IgM antibodies by enzyme-linked immunosorbent assay (ELISA). All measles IgM negative or indeterminate samples were tested for rubella IgM antibody using ELISA. Rubella-IgM-positive samples were tested by real-time reverse transcription polymerase chain reaction (RT-PCR) for the presence of rubella virus RNA. Real-time RT-PCR-positive RNA samples were used as template to amplify the 739 nt region used for rubella genotyping. PCR-positive samples were sequenced and phylogenetic analysis performed. Between 2012 and 2016, 4121 serums and 126 oral fluids were collected through the measles surveillance system. Of these, 3823 and 108 respectively were measles IgM negative or indeterminate. Subsequent testing for rubella found that 690 of 3823 (18%) serum samples and 25 of 108 (23%) oral fluid samples were rubella IgM-positive. The 739 nt segment of the E1 glycoprotein gene was amplified and sequenced for two serums and seven oral fluids samples. Phylogenetic analysis showed that the rubella viruses from CIV belonged to genotypes 1G (eight samples) and 2B (one sample). Rubella virus genotype 2B was found in CIV for the first time. These data contribute to baseline information on rubella virus strains found in CIV before the introduction of rubella vaccine.

High maternal expression of SIGLEC1 on monocytes as a surrogate marker of a type I interferon signature is a risk factor for the development of autoimmune congenital heart block

Objectives

Autoimmune congenital heart block (CHB) is associated with placental transcytosis of maternal autoantibodies directed against Ro/SS-A and La/SS-B. However, only about 2% of children born to mothers with the respective antibodies are affected, indicating that further risk factors exist, which are not yet fully understood. In this study, we investigated whether a maternal type I interferon (IFN) signature represents a risk factor for the development of CHB.

Methods

Blood samples, clinical data and serological parameters from 9 women with CHB pregnancies, 14 pregnant women with antibodies against Ro/SS-A but without a CHB complication and another 30 healthy pregnant women as controls were studied. SIGLEC1 expression was measured by flow cytometry and was correlated to plasma IFN-α levels measured by ELISA, and IFN-γ-induced protein 10 (IP-10) levels measured by Bio-Plex technique.

Results

Mothers of affected children had a significantly higher expression of SIGLEC1 (p=0.0034) and IFN-α (p=0.014), but not of IP-10 (p=0.14, all MWU) compared to mothers of unaffected children. SIGLEC1 and IFN-α expression were reduced by hydroxychloroquine and oral glucocorticoids.

Conclusions

High expression of SIGLEC1 in pregnant women with autoantibodies against Ro/SS-A indicates an enhanced risk for CHB development, and these women may benefit especially from IFN-α directed therapy, for example with hydroxychloroquine.

Epigenetic and transgenerational mechanisms in infection-mediated neurodevelopmental disorders

Prenatal infection is an environmental risk factor for various brain disorders with neurodevelopmental components, including autism spectrum disorder and schizophrenia. Modeling this association in animals shows that maternal immune activation negatively affects fetal brain development and leads to the emergence of behavioral disturbances later in life. Recent discoveries in these preclinical models suggest that epigenetic modifications may be a critical molecular mechanism by which prenatal immune activation can mediate changes in brain development and functions, even across generations. This review discusses the potential epigenetic mechanisms underlying the effects of prenatal infections, thereby highlighting how infection-mediated epigenetic reprogramming may contribute to the transgenerational transmission of pathological traits. The identification of epigenetic and transgenerational mechanisms in infection-mediated neurodevelopmental disorders appears relevant to brain disorders independently of existing diagnostic classifications and may help identifying complex patterns of transgenerational disease transmission beyond genetic inheritance. The consideration of ancestral infectious histories may be of great clinical interest and may be pivotal for developing new preventive treatment strategies against infection-mediated neurodevelopmental disorders.

Fetal malformation in maternal toxoplasma and rubella co-infection in Cameroon: a case report

Background

There has been a recent increase in the number of newborns with brain malformations due to congenital infections, but the impact of these diseases remains largely under ascertained in middle-income and low-income countries. This case report presents a fetal anencephaly following maternal toxoplasma and rubella co-infection in a resource-limited setting and the challenges faced by the patient and the health care provider in the management of the condition.

Case presentation

A 25-year-old black Cameroonian woman of Bakossi origin, gravida₃ para₁010, presented with a positive rubella and toxoplasma immunoglobulin G serologic test at 21 weeks of pregnancy; she could not benefit from a fetal morphologic ultrasound partly because there was none at the site of her antenatal clinic and because there were accessibility constraints getting to the nearest referral hospital approximately 100 km away. She returned to the hospital in labor pains 14 weeks later and, upon examination, she was observed to be at almost full cervical dilatation and had a stillbirth a few minutes later; a baby boy weighing 1600 g with anencephaly.

The devastated parents of the baby were counseled and given psychological support. She was discharged from hospital 3 days later and now benefits from continual follow up as out-patient. She was advised to consult a gynecologist-obstetrician before her next pregnancy.

Conclusion

Much attention still has to be paid to ameliorate the health care in resource-limited settings where pregnant women generally obtain less than adequate care.

Electronic supplementary material

The online version of this article (doi:10.1186/s13256-016-1133-y) contains supplementary material, which is available to authorized users.

A Possible Mechanism of Zika Virus Associated Microcephaly: Imperative Role of Retinoic Acid Response Element (RARE) Consensus Sequence Repeats in the Viral Genome

Owing to the reports of microcephaly as a consistent outcome in the fetuses of pregnant women infected with ZIKV in Brazil, Zika virus (ZIKV)-microcephaly etiomechanistic relationship has recently been implicated. Researchers, however, are still struggling to establish an embryological basis for this interesting causal handcuff. The present study reveals robust evidence in favor of a plausible ZIKV-microcephaly cause-effect liaison. The rationale is based on: (1) sequence homology between ZIKV genome and the response element of an early neural tube developmental marker "retinoic acid" in human DNA and (2) comprehensive similarities between the details of brain defects in ZIKV-microcephaly and retinoic acid embryopathy. Retinoic acid is considered as the earliest factor for regulating anteroposterior axis of neural tube and positioning of structures in developing brain through retinoic acid response elements (RARE) consensus sequence (5'-AGGTCA-3') in promoter regions of retinoic acid-dependent genes. We screened genomic sequences of already reported virulent ZIKV strains (including those linked to microcephaly) and other viruses available in National Institute of Health genetic sequence database (GenBank) for the RARE consensus repeats and obtained results strongly bolstering our hypothesis that ZIKV strains associated with microcephaly may act through precipitation of dysregulation in retinoic acid-dependent genes by introducing extra stretches of RARE consensus sequence repeats in the genome of developing brain cells. Additional support to our hypothesis comes from our findings that screening of other viruses for RARE consensus sequence repeats is positive only for those known to display neurotropism and cause fetal brain defects (for which maternal-fetal transmission during developing stage may be required). The numbers of RARE sequence repeats appeared to match with the virulence of screened positive viruses. Although, bioinformatic evidence and embryological features are in favor of our hypothesis, additional studies including animal models are warranted to validate our proposition. Such studies are likely to unfold ZIKV-microcephaly association and may help in devising methods to combat it.

The global threat of Zika virus to pregnancy: epidemiology, clinical perspectives, mechanisms, and impact

Zika virus (ZIKV) is a mosquito-borne flavivirus that has newly emerged as a significant global threat, especially to pregnancy. Recent major outbreaks in the Pacific and in Central and South America have been associated with an increased incidence of microcephaly and other abnormalities of the central nervous system in neonates. The causal link between ZIKV infection during pregnancy and microcephaly is now strongly supported. Over 2 billion people live in regions conducive to ZIKV transmission, with ~4 million infections in the Americas predicted for 2016. Given the scale of the current pandemic and the serious and long-term consequences of infection during pregnancy, the impact of ZIKV on health services and affected communities could be enormous. This further highlights the need for a rapid global public health and research response to ZIKV to limit and prevent its impact through the development of therapeutics, vaccines, and improved diagnostics. Here we review the epidemiology of ZIKV; the threat to pregnancy; the clinical consequences and broader impact of ZIKV infections; and the virus biology underpinning new interventions, diagnostics, and insights into the mechanisms of disease.