Zika-related adverse outcomes in a cohort of pregnant women with rash in Pernambuco, Brazil.

BACKGROUND: While Zika virus (ZIKV) is now widely recognized as a teratogen, the frequency and full spectrum of adverse outcomes of congenital ZIKV infection remains incompletely understood. METHODS: Participants in the MERG cohort of pregnant women with rash, recruited from the surveillance system from December/2015-June/2017. Exposure definition was based on a combination of longitudinal data from molecular, serologic (IgM and IgG3) and plaque reduction neutralization tests for ZIKV. Children were evaluated by a team of clinical specialists and by transfontanelle ultrasound and were classified as having microcephaly and/or other signs/symptoms consistent with congenital Zika syndrome (CZS). Risks of adverse outcomes were quantified according to the relative evidence of a ZIKV infection in pregnancy. FINDINGS: 376 women had confirmed and suspected exposure to ZIKV. Among evaluable children born to these mothers, 20% presented with an adverse outcome compatible with exposure to ZIKV during pregnancy. The absolute risk of microcephaly was 2.9% (11/376), of calcifications and/or ventriculomegaly was 7.2% (13/180), of additional neurologic alterations was 5.3% (13/245), of ophthalmologic abnormalities was 7% (15/214), and of dysphagia was 1.8% (4/226). Less than 1% of the children experienced abnormalities across all of the domains simultaneously. Interpretation: Although approximately one-fifth of children with confirmed and suspected exposure to ZIKV in pregnancy presented with at least one abnormality compatible with CZS, the manifestations presented more frequently in isolation than in combination. Due to the rare nature of some outcomes and the possibility of later manifestations, large scale individual participant data meta-analysis and the long-term evaluation of children are imperative to identify the full spectrum of this syndrome and to plan actions to reduce damages.

Zika virus infection in pregnancy: Establishing a case definition for clinical research on pregnant women with rash in an active transmission setting.

Defining cases of Zika virus (ZIKV) infection is a critical challenge for epidemiological research. Due to ZIKV's overlapping clinical features and potential immunologic cross-reactivity with other flaviviruses and the current lack of an optimal ZIKV-specific diagnostic assay, varying approaches for identifying ZIKV infections have been employed to date. This paper presents the laboratory results and diagnostic criteria developed by the Microcephaly Epidemic Research Group for defining cases of maternal ZIKV infection in a cohort of pregnant women with rash (N = 694) recruited during the declining 2015-2017 epidemic in northeast Brazil. For this investigation, we tested maternal sera for ZIKV by quantitative reverse transcription polymerase chain reaction (qRT-PCR), Immunoglobulin (Ig) M and IgG3 enzyme-linked immunosorbent assays (ELISAs), and Plaque Reduction Neutralization Test (PRNT50). Overall, 23.8% of participants tested positive by qRT-PCR during pregnancy (range of detection: 0-72 days after rash onset). However, the inter-assay concordance was lower than expected. Among women with qRT-PCR-confirmed ZIKV and further testing, only 10.1% had positive IgM tests within 90 days of rash, and only 48.5% had ZIKV-specific PRNT50 titers ≥20 within 1 year of rash. Given the complexity of these data, we convened a panel of experts to propose an algorithm for identifying ZIKV infections in pregnancy based on all available lines of evidence. When the diagnostic algorithm was applied to the cohort, 26.9% of participants were classified as having robust evidence of a ZIKV infection during pregnancy, 4.0% as having moderate evidence, 13.3% as having limited evidence of a ZIKV infection but with uncertain timing, and 19.5% as having evidence of an unspecified flavivirus infection before or during pregnancy. Our findings suggest that integrating longitudinal data from nucleic acid and serologic testing may enhance diagnostic sensitivity and underscore the need for an on-going dialogue regarding the optimization of strategies for defining cases of ZIKV in research.

Association between microcephaly, Zika virus infection, and other risk factors in Brazil: final report of a case-control study.

BACKGROUND: A Zika virus epidemic emerged in northeast Brazil in 2015 and was followed by a striking increase in congenital microcephaly cases, triggering a declaration of an international public health emergency. This is the final report of the first case-control study evaluating the potential causes of microcephaly: congenital Zika virus infection, vaccines, and larvicides. The published preliminary report suggested a strong association between microcephaly and congenital Zika virus infection. METHODS: We did a case-control study in eight public maternity hospitals in Recife, Brazil. Cases were neonates born with microcephaly, defined as a head circumference of 2 SD below the mean. Two controls without microcephaly were matched to each case by expected date of delivery and area of residence. We tested the serum of cases and controls and the CSF of cases for detection of Zika virus genomes with quantitative RT-PCR and for detection of IgM antibodies with capture-IgM ELISA. We also tested maternal serum with plaque reduction neutralisation assays for Zika and dengue viruses. We estimated matched crude and adjusted odds ratios with exact conditional logistic regression to determine the association between microcephaly and Zika virus infection. FINDINGS: We screened neonates born between Jan 15 and Nov 30, 2016, and prospectively recruited 91 cases and 173 controls. In 32 (35%) cases, congenital Zika virus infection was confirmed by laboratory tests and no controls had confirmed Zika virus infections. 69 (83%) of 83 cases with known birthweight were small for gestational age, compared with eight (5%) of 173 controls. The overall matched odds ratio was 73·1 (95% CI 13·0-∞) for microcephaly and Zika virus infection after adjustments. Neither vaccination during pregnancy or use of the larvicide pyriproxyfen was associated with microcephaly. Results of laboratory tests for Zika virus and brain imaging results were available for 79 (87%) cases; within these cases, ten were positive for Zika virus and had cerebral abnormalities, 13 were positive for Zika infection but had no cerebral abnormalities, and 11 were negative for Zika virus but had cerebral abnormalities. INTERPRETATION: The association between microcephaly and congenital Zika virus infection was confirmed. We provide evidence of the absence of an effect of other potential factors, such as exposure to pyriproxyfen or vaccines (tetanus, diphtheria, and acellular pertussis, measles and rubella, or measles, mumps, and rubella) during pregnancy, confirming the findings of an ecological study of pyriproxyfen in Pernambuco and previous studies on the safety of Tdap vaccine administration during pregnancy. FUNDING: Brazilian Ministry of Health, Pan American Health Organization, and Enhancing Research Activity in Epidemic Situations.

Clinical and laboratory diagnosis of congenital Zika virus syndrome and diaphragmatic unilateral palsy: case report / Diagnostico clínico e laboratorial do Zika vírus congênito e paralisia diafragmática unilateral: o relato de um caso

Abstract Introduction: several birth defects associated to congenital Zika virus infection have been reported, although the clinical features have not been fully characterized. Description: this is the first case report on unilateral diaphragmatic paralysis diagnosed on a neonate with congenital Zika confirmed by the examination of the amniotic fluid through polymerase chain reaction (ZIKV RT-PCR) and the examination of cerebrospinal fluid by serological test (IgM ZIKV-ELISA) after birth. The main manifestations detected by intrauterine ultrasound were: microcephaly, ventriculomegaly, intracranial calcifications, enlarged cisterna magna, increased amniotic fluid index and fetal akinesia syndrome. The newborn had acute respiratory failure in the first hours of life, requiring mechanical ventila-tion. The X- ray of the chest showed unilateral diaphragmatic paralysis and cardiomegaly. Discussion: diaphragmatic palsy in congenital Zika has not been previously reported, the etiopathogenic mechanisms of this event in congenital Zika virus needs to be elucidated.

Resumo Introdução: apesar de vários defeitos de nascimento associados à infecção congênita pelo Zika vírus terem sido descritos, o quadro clínico ainda não foi completamente caracterizado. Descrição: este é o primeiro relato de caso de paralisia diafragmática unilateral em um neonato com diagnóstico confirmado de Zika congênita pelo exame do líquido amniótico utilizando a reação da polimerase em cadeia (ZIKV PCR-RT) e pelo exame sorológico do líquido cefaloraquidiano (ZIKV IgM-ELISA), após o nascimento. As principais manifestações detectadas pela ultrassonografia intraútero no período gestacional foram: microcefalia, ventriculomegalia, calcificações intracranianas, cisterna magna alargada, aumento do índice de liquido amniótico e síndrome da acinesia fetal. O recém-nascido apresentou falência respiratória aguda nas primarias horas de vida, necessitando de ventilação mecânica. A radiografia de tórax realizada mostrou paralisia diafragmática unilateral e cardiomegalia. Discussão: a paralisia diafragmática na Zika congênita não havia sido previamente relatada, havendo a necessidade de investigação dos mecanismos etiopatogênicos dessa manifestação na infecção congênita pelo Zika vírus.

Transferência placentária e cinética de anticorpos antidengue materno transferidos em uma coorte de crianças no primeiro ano de vida / Placental transfer and kineticis of maternal transferred dengue-specific antibodies in a cohort of children during the first year

Anticorpos antidengue materno transferidos têm sido implicados na imunopatogênese da dengue grave em lactentes. Postula-se que esses anticorpos possuam um papel distinto durante os primeiros anos de vida: ao nascimento, anticorpos antidengue materno adquiridos conferem proteção, e em seguida declinam a níveis subneutralizantes capazes de facilitar a infecção pelo vírus dengue (DENV) mediante o mecanismo de ADE (Antibody dependent enhancement), aumentando o risco de ocorrência das formas graves da dengue. Estudos prospectivos conduzidos em lactentes Asiáticos têm mostrado que o pico de anticorpos materno adquiridos com a capacidade de mediar aumento da infecção pelo DENV ocorre entre o sexto e o nono mês de vida, o que correlaciona com a epidemiologia da dengue grave em lactentes dessa região. Esta tese descreve o perfil de imunidade materna antidengue e a transferência placentária de anticorpos dengue-específicos em pares mãe-cordão recrutados em um estudo de coorte prospectivo conduzido na cidade do Recife, Nordeste do Brasil. Adicionalmente, esse trabalho analisa o papel dos níveis de IgG total maternos e da imunidade antidengue materna na transferência de anticorpos ao feto. Na coorte de lactentes, a tese avalia a cinética de declínio dos anticorpos antidengue materno-transferidos e sua capacidade de mediar ADE durante os primeiros anos de vida. Níveis de IgG DENV-especifico e de anticorpos neutralizantes sorotipo específicos (DENV1-4) foram determinados em 376 pares mãe-cordão. A cinética de anticorpos materno transferidos neutralizantes e/ou mediadores de ADE foi investigada em uma subamostra das crianças inseridas na coorte. A maior parte das gestantes apresentava imunidade ao sorotipo DENV-3 (53,7 por cento) ou a combinação DENV-3/ DENV-4 (30,6 por cento)...

Maternal-fetal transferred Dengue virus (DENV)-specific antibodies have been implicated in the immunopathogenesis of dengue during infancy. These antibodies play a dual role in infants during the first year of life: first, maternally-acquired antibodies confer protection at birth, and then decline to a lower level capable of enhance DENV infection through the mechanism of ADE (antibody-dependent enhancement), increasing the chance of development of severe dengue. Prospective studies conducted in Asian infants have provided evidence that the peak of enhancing activity by maternally transferred dengue antibodies occurs between 6th to 9th month of age, which correlates with the age-related epidemiology of the dengue severe cases in this region. This thesis describes the placental transfer of dengue-specific antibodies in mother-cord pairs enrolled in a prospective cohort study carried out in the city of Recife, Northeast Brazil. Moreover, we analyze the role of maternal total IgG levels and dengue immunity in the transference of dengue-specific antibodies to the fetus. In the cohort of children, we determine the kinetics of Enhancing Activity (EA) by maternally acquired dengue antibodies during their first year of life. DENV-specific IgG and serotype-specific (DENV1-4) neutralizing antibody (Nab) levels were assessed in 376 mother-cord paired samples...