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The relation of Zika virus (ZIKV) with microcephaly is well established. However, knowledge is lacking on later developmental outcomes in children with evidence of maternal ZIKV infection during pregnancy born without microcephaly. The objective of this analysis is to investigate the impact of prenatal exposure to ZIKV on neuropsychomotor development in children without microcephaly. We evaluated 274 children including 235 ZIKV exposed and 39 controls using the Bayley-III Scales of Infant and Toddler Development (BSIDIII) and neurological examination. We observed a difference in cognition with a borderline p-value (p = 0.052): 9.4% of exposed children and none of the unexposed control group had mild to moderate delays. The prevalence of delays in the language and motor domains did not differ significantly between ZIKV-exposed and unexposed children (language: 12.3% versus 12.8%; motor: 4.7% versus 2.6%). Notably, neurological examination results were predictive of neurodevelopmental delays in the BSIDIII assessments for exposed children: 46.7% of children with abnormalities on clinical neurological examination presented with delay in contrast to 17.8% among exposed children without apparent neurological abnormalities (p = 0.001). Overall, our findings suggest that relative to their unexposed peers, ZIKV-exposed children without microcephaly are not at considerably increased risk of neurodevelopmental impairment in the first 42 months of life, although a small group of children demonstrated higher frequencies of cognitive delay. It is important to highlight that in the group of exposed children, an abnormal neuroclinical examination may be a predictor of developmental delay. The article contributes to practical guidance and advances our knowledge about congenital Zika.

Despite great advances in our knowledge of the consequences of Zika virus to human health, many questions remain unanswered, and results are often inconsistent. The small sample size of individual studies has limited inference about the spectrum of congenital Zika manifestations and the prognosis of affected children. The Brazilian Zika Cohorts Consortium addresses these limitations by bringing together and harmonizing epidemiological data from a series of prospective cohort studies of pregnant women with rash and of children with microcephaly and/or other manifestations of congenital Zika. The objective is to estimate the absolute risk of congenital Zika manifestations and to characterize the full spectrum and natural history of the manifestations of congenital Zika in children with and without microcephaly. This protocol describes the assembly of the Consortium and protocol for the Individual Participant Data Meta-analyses (IPD Meta-analyses). The findings will address knowledge gaps and inform public policies related to Zika virus. The large harmonized dataset and joint analyses will facilitate more precise estimates of the absolute risk of congenital Zika manifestations among Zika virus-infected pregnancies and more complete descriptions of its full spectrum, including rare manifestations. It will enable sensitivity analyses using different definitions of exposure and outcomes, and the investigation of the sources of heterogeneity between studies and regions.

This cohort profile aims to describe the ongoing follow-up of children in the Microcephaly Epidemic Research Group Paediatric Cohort (MERG-PC). The profile details the context and aims of the study, study population, methodology including assessments, and key results and publications to date. The children that make up MERG-PC were born in Recife or within 120 km of the city, in Pernambuco/Brazil, the epicentre of the microcephaly epidemic. MERG-PC includes children from four groups recruited at different stages of the ZIKV microcephaly epidemic in Pernambuco, i.e., the Outpatient Group (OG/n = 195), the Microcephaly Case-Control Study (MCCS/n = 80), the MERG Pregnant Women Cohort (MERG-PWC/n = 336), and the Control Group (CG/n = 100). We developed a comprehensive array of clinical, laboratory, and imaging assessments that were undertaken by a 'task force' of clinical specialists in a single day at 3, 6, 12, 18 months of age, and annually from 24 months. Children from MCCS and CG had their baseline assessment at birth and children from the other groups, at the first evaluation by the task force. The baseline cohort includes 711 children born between February 2015 and February 2019. Children's characteristics at baseline, excluding CG, were as follows: 32.6% (184/565) had microcephaly, 47% (263/559) had at least one physical abnormality, 29.5% (160/543) had at least one neurological abnormality, and 46.2% (257/556) had at least one ophthalmological abnormality. This ongoing cohort has contributed to the understanding of the congenital Zika syndrome (CZS) spectrum. The cohort has provided descriptions of paediatric neurodevelopment and early epilepsy, including EEG patterns and treatment response, and information on the frequency and characteristics of oropharyngeal dysphagia; cryptorchidism and its surgical findings; endocrine dysfunction; and adenoid hypertrophy in children with Zika-related microcephaly. The study protocols and questionnaires were shared across Brazilian states to enable harmonization across the different studies investigating microcephaly and CZS, providing the opportunity for the Zika Brazilian Cohorts Consortium to be formed, uniting all the ZIKV clinical cohorts in Brazil.

Resumo: A pandemia de COVID-19 iniciou sua linha do tempo em 31 de dezembro de 2019 na China e o SARS-CoV-2 identificado como agente etiológico. O objetivo deste manuscrito é descrever a dinâmica espacial e temporal da epidemia de COVID-19 nos primeiros cem dias, no Estado de Pernambuco, Brasil. Apresentamos a evolução de casos e óbitos segundo semana epidemiológica. Realizamos a análise da série do acumulado diário de casos da COVID-19 confirmados, com projeções para os 15 dias subsequentes, utilizando o aplicativo JoinPoint. Esse programa possibilita identificar pontos de inflexão testando sua significância estatística. Analisamos também a tendência de interiorização da COVID-19 no estado, considerando a distribuição percentual de casos ocorridos no Recife, municípios da Região Metropolitana de Recife e do interior, por conjuntos de três semanas, com construção de mapas temáticos. Os 100 dias da epidemia de COVID-19 resultaram em 52.213 casos e 4.235 óbitos entre 12 de março, correspondendo se 11, até 20 de junho de 2020 (semana epidemiológica 25). O pico da curva epidêmica ocorreu na semana epidemiológica 21 (23 de maio), seguido por desaceleração do número de casos. Detectou-se, inicialmente, a periferização dos casos na capital e região metropolitana, seguida por rápida disseminação para o interior do estado. Houve redução das taxas de crescimento médio diário a partir de abril, mas com patamar de mais de 6.000 casos semanais de COVID-19, em média. Ao final do período, a série de casos do estado indica persistência da circulação e transmissão comunitária do SARS-CoV-2. Finalmente, questiona-se parafraseando Garcia Marques em Cem Anos de Solidão, se estaríamos diante de “uma estiagem ou prenúncio de recrudescimento”. Resumen: La pandemia de COVID-19 inicia su línea del tiempo el 31 de dicembre de 2019 en China y el SARS-CoV-2 identificado como agente etiológico. El objetivo de este trabajo original es describir la dinámica espacial y temporal de la epidemia de COVID-19 en los primeros cien días de epidemia, en el estado de Pernambuco, Brasil. Presentamos la evolución de casos y óbitos según las semanas epidemiológicas. Realizamos el análisis de la serie del acumulado diario de casos de COVID-19 confirmados, con proyecciones para los 15 días subsiguientes, utilizándose la aplicación JoinPoint. Este programa posibilita identificar puntos de inflexión, probando su significancia estadística. Analizamos también la tendencia de interiorización de la COVID-19 en el estado, considerándose la distribución porcentual de casos ocurridos en Recife, municipios de la Región Metropolitana de Recife y del interior, por conjuntos de tres semanas, con unas construcciones de mapas temáticos. Los cien días de la epidemia de COVID-19 resultaron en 52.213 casos y 4.235 óbitos entre el 12 de marzo, correspondiendo a la semana epidemiológica 11, hasta el 20 de juno de 2020 (semana epidemiológica 25). El pico de la curva epidémica ocurrió en la semana epidemiológica 21 (23 de mayo), seguido de una desaceleración en el número de casos. Se detectó, inicialmente, la periferización de los casos en la capital y región metropolitana, seguido por la rápida diseminación hacia el interior del estado. Hubo una reducción de las tasas de crecimiento medio diario a partir de abril, pero con un nivel de más de 6.000 casos semanales de COVID-19 de media. Al final del período la serie de casos del estado indica la persistencia de la circulación y transmisión comunitaria del SARS-CoV-2. Finalmente, se cuestiona, parafraseando a García Márquez en Cien Años de Soledad, si estamos ante “un periodo de remisión o la antesala de un recrudecimiento”. Abstract: The timeline of the COVID-19 pandemic began on December 31, 2019, in China, with SARS-CoV-2 identified as the etiological agent. This article aims to describe the COVID-19 epidemic’s spatial and temporal dynamics in the first hundred days in the State of Pernambuco, Brazil. We present the evolution in cases and deaths according to epidemiological weeks. We analyzed the series of accumulated daily confirmed COVID-19 cases, with projections for the subsequent 15 days, using the JoinPoint app. This software allows identifying turning points, testing their statistical significance. We also analyze the trend in the spread of COVID-19 to the interior of the state, considering the percent distribution of cases in the state capital, Recife, municipalities in Greater Metropolitan Recife, and the state’s interior, by sets of three weeks, constructing thematic maps. The first hundred days of the COVID-19 epidemic resulted in 52,213 cases and 4,235 deaths from March 12, or epidemiological week 11, until June 20, 2020 (epidemiological week 25). The peak in the epidemic curve occurred in epidemiological week 21 (May 23), followed by deceleration in the number of cases. We initially detected the spread of cases from the city center to the periphery of the state capital and Metropolitan Area, followed by rapid spread to the state’s interior. There was a decrease in the mean daily growth starting in April, but with an average threshold of more than 6,000 weekly cases of COVID-19. At the end of the period, the state’s case series indicates the persistence of SARS-CoV-2 circulation and community transmission. Finally, paraphrasing Gabriel Garcia Marques in One Hundred Years of Solitude, we ask whether we are facing “a pause in the storm or a sign of redoubled rain”.

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.

Em agosto de 2015, neuropediatras de hospitais públicos do Recife, Pernambuco, Brasil, observaram um aumento do número de casos de microcefalia desproporcional associado a anomalias cerebrais. Esse fato gerou comoção social, mobilização da comunidade acadêmica e levou o Ministério da Saúde a decretar emergência de saúde pública nacional, seguida pela declaração de emergência de saúde pública de interesse internacional da Organização Mundial da Saúde. A hipótese formulada para o fenômeno foi a infecção congênita pelo vírus Zika (ZIKV), com base na correlação espaço-temporal e nas características clínico-epidemiológicas das duas epidemias. Evidências se acumularam e no âmbito do raciocínio epidemiológico preencheram critérios que deram sustentação à hipótese. Sua plausibilidade está ancorada no neurotropismo do ZIKV demonstrado em animais, atingindo neurônios progenitores do cérebro em desenvolvimento, e em seres humanos devido às complicações neurológicas observadas em adultos após a infecção. O isolamento do RNA e antígenos virais no líquido amniótico de mães infectadas e em cérebros de neonatos e fetos com microcefalia contribuíram para demonstrar a consistência da hipótese. O critério de temporalidade foi contemplado ao se identificar desfechos desfavoráveis em uma coorte de gestantes com exantema e positivas para o ZIKV. Finalmente, o primeiro estudo caso-controle conduzido demonstrou existir uma forte associação entre microcefalia e infecção congênita pelo ZIKV. O conhecimento construído no âmbito do paradigma epidemiológico recebeu a chancela da comunidade científica, construindo o consenso de uma relação causal entre o ZIKV e a epidemia de microcefalia. En agosto de 2015, neuropediatras de hospitales públicos de Recife, Pernambuco, Brasil, observaron un aumento desproporcional del número de casos de microcefalia, asociado a anomalías cerebrales. Este hecho generó conmoción social, movilización de la comunidad académica y obligó al Ministerio de Salud a decretar la emergencia de salud pública nacional, seguida de la declaración de interés internacional de la Organización Mundial de la Salud. La hipótesis formulada para este fenómeno fue la infección congénita por el virus Zika (ZIKV), en base a la correlación espacio-temporal y a las características clínico-epidemiológicas de las dos epidemias. Se acumularon evidencias, y en el ámbito del raciocinio epidemiológico se cumplieron los criterios que dieron apoyo a la hipótesis. Su plausibilidad está anclada en el neurotropismo del ZIKV, demostrado en animales, alcanzando progenitores neuronales del cerebro en desarrollo, y en seres humanos, debido a las complicaciones neurológicas observadas en adultos tras la infección. El aislamiento del ARN y antígenos virales en el líquido amniótico de madres infectadas, en cerebros de neonatos y fetos con microcefalia, contribuyeron a demostrar la consistencia de la hipótesis. El criterio de temporalidad se contempló al identificarse desenlaces desfavorables en una cohorte de gestantes con exantema y positivas en ZIKV. Finalmente, el primer estudio caso-control realizado demostró que existía una fuerte asociación entre microcefalia e infección congénita por el ZIKV. El conocimiento construido en el ámbito del paradigma epidemiológico recibió la aprobación de la comunidad científica, existiendo consenso en cuanto a la relación causal entre el ZIKV y la epidemia de microcefalia. In August 2015, pediatric neurologists at public hospitals in Recife, Pernambuco State, Brazil, observed an increase in the number of disproportional microcephaly cases associated with other congenital anomalies. The fact caused social commotion and mobilization of the academic community and led the Brazilian Ministry of Health to declare a national public health emergency, followed by the declaration of a Public Health Emergency of International Concern by the World Health Organization. The hypothesis for the phenomenon was congenital Zika virus (ZIKV) infection, based on spatial-temporal correlation and the clinical-epidemiological characteristics of the two epidemics. Further evidence accumulated, and within the scope of epidemiologial reasoning fulfilled criteria that gave support to the hypothesis. The plausibility of the hypothesis is based on the neurotropism of ZIKV, demonstrated in animals, affecting neural progenitors in the developing brain, and in humans, due to neurological complications in adults following infection. Isolation of viral RNA and antigens in the amniotic fluid of infected mothers and in brains of newborns and fetuses with microcephaly further demonstrated the consistency of the hypothesis. The criterion of temporality was met by identifying adverse pregnancy outcomes in a cohort of mothers with a history of rash and positive ZIKV serology. Finally, the first case-control study demonstrated a strong association between microcephaly and congenital ZIKV infection. The knowledge built with the epidemiological paradigm was supported by the scientific community, thereby establishing the consensus for a causal relationship between ZIKV and the microcephaly epidemic.

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.