Growth and Survival of a Cohort of Congenital Zika Virus Syndrome Children Born With Microcephaly and Children Who Developed With Microcephaly After Birth.

Abstract

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.