Heterogeneous development of children with Congenital Zika Syndrome-associated microcephaly.

OBJECTIVE: To describe the neurological and neurodevelopmental outcomes of children with Congenital Zika Syndrome (CZS) associated microcephaly beyond 2 years of age. METHOD: We followed children with CZS-associated microcephaly in an outpatient clinic in Salvador, Brazil. Neurological and neurodevelopmental assessments were performed using the Hammersmith Infant Neurological Examination (HINE) and Bayley Scales of Infant and Toddler Neurodevelopment (Bayley-III) respectively. RESULTS: Of the 42 children included, 19 were male (45.2%); median (interquartile range) age at neurological evaluation was 28 (25-32) months, and 36 (85.7%) had severe microcephaly. HINE and Bayley-III results were completed for 35/42 (83.3%) and 33/42 (78.5%) children respectively. Bayley-III identified a severe developmental delay in 32/33 (97.0%) children while 1/33 (3.0%) had only a mild delay. In the multivariable analysis, we found that Bayley-III and HINE scores were correlated. Better HINE scores were associated with higher Bayley-III cognitive raw scores (ß = 0.29; CI 95% = 0.02-0.57) and motor raw scores (ß = 0.43; CI 95% = 0.04-0.82) after adjusting for head circumference, prematurity, and age at neurodevelopmental evaluation. Furthermore, we found that greater head circumference at follow up was associated with higher cognitive (ß = 1.27; CI 95% = 0.01-2.53) and motor raw scores (ß = 2.03; CI 95% = 0.25-3.81). CONCLUSION: Children with CZS-associated microcephaly demonstrate severe neurodevelopmental delays and slower growth rates than their peers over time. Still, they have remarkably heterogeneous neurodevelopmental profiles according to neurological exam scores which correlate with their long-term outcomes. We found that HINE scores effectively captured the heterogeneity of neurological capabilities among these children and could be predictive of cognitive and motor development progress.

Developmental outcomes in children exposed to Zika virus in utero from a Brazilian urban slum cohort study.

BACKGROUND: The prevalence of developmental alterations associated with in-utero Zika virus (ZIKV) exposure in children is not well understood. Furthermore, estimation of the Population Attributable Fraction (PAF) of developmental alterations attributed to ZIKV has not been performed due to lack of population-based cohorts with data on symptomatic and asymptomatic ZIKV exposures and an appropriate control group. The aim of this study was to characterize neurodevelopmental outcomes of children at 11 to 32 months of age with intrauterine ZIKV exposure and estimate the PAF of alterations secondary to ZIKV exposure. METHODOLOGY/PRINCIPAL FINDINGS: We performed a cohort of biannual community-based prospective serosurveys in a slum community in Salvador, Brazil. We recruited women participating in our cohort, with a documented pregnancy from January 2015 to December 2016 and children born to those mothers. Children were classified as ZIKV exposed in utero (born from women with ZIKV seroconversion during pregnancy) or unexposed (born from women without ZIKV seroconversion or that seroconverted before/after pregnancy) by using an IgG monoclonal antibody blockade-of-binding (BoB). We interviewed mothers and performed anthropometric, audiometric, ophthalmological, neurologic, and neurodevelopmental evaluations of their children at 11 to 32 months of age. Among the 655 women participating in the cohort, 66 (10%) were pregnant during the study period. 46 (70%) of them completed follow-up, of whom ZIKV seroconversion occurred before, during, and after pregnancy in 25 (54%), 13 (28%), and 1 (2%), respectively. The rest of women, 7 (21.2%), did not present ZIKV seroconversion. At 11 to 32 months of life, the 13 ZIKV-exposed children had increased risk of mild cognitive delay (RR 5.1; 95%CI 1.1-24.4) compared with the 33 children unexposed, with a PAF of 53.5%. Exposed children also had increased risk of altered auditory behavior (RR 6.0; 95%CI 1.3-26.9), with a PAF of 59.5%. CONCLUSIONS: A significant proportion of children exposed in utero to ZIKV developed mild cognitive delay and auditory behavioral abnormalities even in the absence of gross birth defects such as microcephaly and other neurodevelopmental domains. Furthermore, our findings suggest that over half of these abnormalities could be attributed to intrauterine ZIKV exposure.

Risk of Zika microcephaly correlates with features of maternal antibodies.

Zika virus (ZIKV) infection during pregnancy causes congenital abnormalities, including microcephaly. However, rates vary widely, and the contributing risk factors remain unclear. We examined the serum antibody response to ZIKV and other flaviviruses in Brazilian women giving birth during the 2015-2016 outbreak. Infected pregnancies with intermediate or higher ZIKV antibody enhancement titers were at increased risk to give birth to microcephalic infants compared with those with lower titers (P < 0.0001). Similarly, analysis of ZIKV-infected pregnant macaques revealed that fetal brain damage was more frequent in mothers with higher enhancement titers. Thus, features of the maternal antibodies are associated with and may contribute to the genesis of ZIKV-associated microcephaly.

Zika and the Eye: Pieces of a Puzzle.

Zika virus (ZIKV) is an arbovirus mainly transmitted to humans by mosquitoes from Aedes genus. Other ways of transmission include the perinatal and sexual routes, blood transfusion, and laboratory exposure. Although the first human cases were registered in 1952 in African countries, outbreaks were only reported since 2007, when entire Pacific islands were affected. In March 2015, the first cases of ZIKV acute infection were notified in Brazil and, to date, 48 countries and territories in the Americas have confirmed local mosquito-borne transmission of ZIKV. Until 2015, ZIKV infection was thought to only cause asymptomatic or mild exanthematous febrile infections. However, after explosive ZIKV outbreaks in Polynesia and Latin American countries, it was confirmed that ZIKV could also lead to Guillain-Barré syndrome and congenital birth abnormalities. These abnormalities, which can include neurologic, ophthalmologic, audiologic, and skeletal findings, are now considered congenital Zika syndrome (CZS). Brain abnormalities in CZS include cerebral calcifications, malformations of cortical development, ventriculomegaly, lissencephaly, hypoplasia of the cerebellum and brainstem. The ocular findings, which are present in up to 70% of infants with CZS, include iris coloboma, lens subluxation, cataract, congenital glaucoma, and especially posterior segment findings. Loss of retinal pigment epithelium, the presence of a thin choroid, a perivascular choroidal inflammatory infiltrate, and atrophic changes within the optic nerve were seen in histologic analyses of eyes from deceased fetuses. To date, there is no ZIKV licensed vaccines or antiviral therapies are available for treatment. Preventive measures include individual protection from mosquito bites, control of mosquito populations and the use of barriers measures such as condoms during sexual intercourse or sexual abstinence for couples either at risk or after confirmed infection. A literature review based on studies that analyzed ocular findings in mothers and infants with CZS, with or without microcephaly, was conducted and a theoretical pathophysiologic explanation for ZIKV-ocular abnormalities was formulated.

INFANTS WITH CONGENITAL ZIKA SYNDROME AND OCULAR FINDINGS FROM SÃO PAULO, BRAZIL: SPREAD OF INFECTION.

BACKGROUND/PURPOSE: To describe the ocular findings of two infants with congenital Zika syndrome born in São Paulo state, Brazil, outside the primary outbreak region. METHODS: Two female infants with congenital Zika syndrome were submitted to a complete screening for infectious diseases, as well as ocular examination, fundus photography, and optical coherence tomography of the retina. One of the infants was submitted to ocular ultrasound. RESULTS: Both children showed positive serology for Zika virus, and other infectious diseases were ruled out. On fundus examination, one newborn had extensive bilateral macular chorioretinal atrophy with hyperpigmented borders associated with gross pigment mottling, as well as atrophic well-limited roundish peripheral lesions in the right eye. Spectral domain optical coherence tomography of the right eye showed complete chorioretinal atrophy in the temporal quadrant. The other infant presented bilateral gross pigment mottling in a paramacular location and a normal optical coherence tomography. DISCUSSION: In this report, the ophthalmologic findings of two infants with Zika syndrome and ocular findings born in São Paulo state, Brazil, are described. Optical coherence tomography findings demonstrate the broad range of retinal damage caused by congenital Zika virus infection. CONCLUSION: The autochthonous cases of infants with congenital Zika syndrome and ocular findings described in this report demonstrate that Zika virus infection is not limited to northeast Brazil, with the potential for even greater spread.

Zika virus and the eye.

PURPOSE OF REVIEW: The aim of this study was to review the ocular findings related to the Zika virus (ZIKV) based on the main studies published to date, describe the patterns of the lesions and risk factors, and identify the public health implications and scientific importance of this emerging disease. RECENT FINDINGS: In most studies, the ZIKV seems related to congenital ocular lesions and most mothers reported mild symptoms during the first pregnancy trimester. Five fundus patterns were seen most often: macular chorioretinal atrophy, chorioretinal atrophy elsewhere, focal pigmentary changes in the macular region, optic nerve abnormalities and combined types. A few studies have suggested that the ZIKV might damage the anterior segment of these babies' eyes. Few reports have described the ocular complications seen in adults during the acute infection, including conjunctivitis, iridocyclitis and chorioretinitis. SUMMARY: Infants with congenital Zika syndrome might have vision-threatening fundus abnormalities. Although the full spectrum of ocular lesions caused by the ZIKV infection is not yet determined, a distinctive new disease has been observed. Recognition of these lesions by ophthalmologists can help ensure appropriate etiologic evaluation and clinical investigation to define the range of anomalies in an affected infant and determine essential follow-up and ongoing care.

Ocular Findings in Infants With Microcephaly Associated With Presumed Zika Virus Congenital Infection in Salvador, Brazil.

IMPORTANCE: The Zika virus (ZIKV) has rapidly reached epidemic proportions, especially in northeastern Brazil, and has rapidly spread to other parts of the Americas. A recent increase in the prevalence of microcephaly in newborn infants and vision-threatening findings in these infants is likely associated with the rapid spread of ZIKV. OBJECTIVE: To evaluate the ocular findings in infants with microcephaly associated with presumed intrauterine ZIKV infection in Salvador, Bahia, Brazil. DESIGN, SETTING, AND PARTICIPANTS: Case series at a tertiary hospital. Twenty-nine infants with microcephaly (defined by a cephalic circumference of ≤32 cm) with a presumed diagnosis of congenital ZIKV were recruited through an active search and referrals from other hospitals and health unities. The study was conducted between December 1 and December 21, 2015. INTERVENTIONS: All infants and mothers underwent systemic and ophthalmic examinations from December 1 through December 21, 2015, in the Roberto Santos General Hospital, Salvador, Brazil. Anterior segment and retinal, choroidal, and optic nerve abnormalities were documented using a wide-field digital imaging system. The differential diagnosis included toxoplasmosis, rubella, cytomegalovirus, herpes simplex virus, syphilis, and human immunodeficiency virus, which were ruled out through serologic and clinical examinations. MAIN OUTCOMES AND MEASURES: Ocular abnormalities associated with ZIKV. RESULTS: Twenty-three of 29 mothers (79.3%) reported suspected ZIKV infection signs and symptoms during pregnancy, 18 in the first trimester, 4 in the second trimester, and 1 in the third trimester. Of the 29 infants (58 eyes) examined (18 [62.1%] female), ocular abnormalities were present in 17 eyes (29.3%) of 10 children (34.5%). Bilateral findings were found in 7 of 10 patients presenting with ocular lesions, the most common of which were focal pigment mottling of the retina and chorioretinal atrophy in 11 of the 17 eyes with abnormalities (64.7%), followed by optic nerve abnormalities in 8 eyes (47.1%), bilateral iris coloboma in 1 patient (2 eyes [11.8%]), and lens subluxation in 1 eye (5.9%). CONCLUSIONS AND RELEVANCE: Congenital infection due to presumed ZIKV exposure is associated with vision-threatening findings, which include bilateral macular and perimacular lesions as well as optic nerve abnormalities in most cases.