An outbreak of births of microcephalic patients in Brazil motivated multiple studies on this incident. The data left no doubt that infection by Zika virus (ZIKV) was the cause, and that this virus promotes reduction in neuron numbers and neuronal death. Analysis of patients' characteristics revealed additional aspects of the pathology alongside the decrease in neuronal number. Here, we review the data from human, molecular, cell and animal model studies attempting to build the natural history of ZIKV in the embryonic central nervous system (CNS). We discuss how identifying the timing of infection and the pathways through which ZIKV may infect and spread through the CNS can help explain the diversity of phenotypes found in congenital ZIKV syndrome (CZVS). We suggest that intraneuronal viral transport is the primary mechanism of ZIKV spread in the embryonic brain and is responsible for most cases of CZVS. According to this hypothesis, the viral transport through the blood–brain barrier and cerebrospinal fluid is responsible for more severe pathologies in which ZIKV-induced malformations occur along the entire anteroposterior CNS axis.
The Zika virus was responsible for an outbreak between 2015 and 2016 in Brazil: an alarming public health problem of international relevance. The Congenital Zika Syndrome (CZS) is often associated with manifestations that are responsible for cognitive and motor development delays and behavioral disorders. Thus, we aimed to characterize the clinical-epidemiological and familial context of those children and to identify factors associated with the risk of behavioral disorders using the Survey of Well-Being of Young Children questionnaire (SWYC). In total, 52 children diagnosed with CZS were evaluated. Logistic regressions were employed to assess predictive variables for behavioral alteration. Eighteen (35%) of the children presented a risk of behavioral alteration. Children born normocephalic were 36-fold more likely to present behavioral alteration (95% CI: 3.82 to 337.92, p = 0.002). Children with hearing and visual impairments showed reduced risks. In total, 35% percent of families reported food insecurity and 21% were at risk for maternal depression. Our findings suggest better social interactions and conditions to externalize reactions for children with CZS born normocephalic. The continuous assessment of these children and families may identify conditions associated with behavioral alteration and psychosocial vulnerabilities that help in decision-making, therefore optimizing patient–family interactions.
24 January 2025 in The Pediatric Infectious Disease Journal
Background and objectives: Little is known about the clinical course of children born with congenital Zika virus syndrome (CZS). This article aimed to analyze the growth and survival of children with CZS born with microcephaly and children who developed with microcephaly after birth in the 36-month period. Methods: This is a cohort of children diagnosed with CZS who were monitored in a series of outpatient appointments, with clinical and demographic information and anthropometric measurements collected. The Mann-Kendall test evaluated the trend of the mean Z-score of head circumference (HC) for age and the Kaplan-Meier model described the time to low weight and short length according to the classification of HC at birth. Results: Children born without microcephaly had a reduction in HC growth velocity (P = 0.019) and took longer to reach low weight (P = 0.036) and short length (P = 0.034) when compared with those born with microcephaly. Seven (10%) deaths were reported, and the probability of survival after 36 months of age was 88%. In children with arthrogryposis, the risk of death was 7 times as high as in those without this condition (adjusted hazard ratio: 6.49; 95% confidence interval: 1.31–32.20; P = 0.022). Conclusions: In this cohort of children with CZS, 20% were born without microcephaly and all of them presented a reduction in HC growth velocity, which led to microcephaly. Progression to low weight and short length occurred in the first years of life, and that was faster in those born with microcephaly. Healthcare providers should be aware of these conditions that pose a risk of unfavorable anthropometric measurements and death.