Neurodevelopmental Outcomes in Children Vertically Exposed to Chikungunya Virus: A Two Years Follow-up Study

To monitor by the first 24 months of life, children born to mothers with laboratory evidence of chikungunya virus (CHIKV) infection during pregnancy or up to 8 weeks before it, and to describe abnormalities in head circumference (HC), auditory and ophthalmological assessments and neuroimaging tests during the follow-up period.

This is a observational, descriptive, longitudinal and prospective study of children born to mothers who had a rash and a positive test for CHIKV during pregnancy or up to 8 weeks before it. They were admitted between November 2015 and May 2019 in the outpatient multidisciplinary clinic to investigate acute exanthematous disease. The exposed children were followed up by a multidisciplinary team and underwent periodic measurements of the HC. The Denver II test was applied, in addition to transfontanellar ultrasound (TU) to evaluate neurodevelopmental outcomes during the study period. Ophthalmological and auditory examinations, echocardiography and laboratory tests were also included.

We included in the study 27 children vertically exposed to CHIKV. All children had a negative polymerase chain reaction test for the virus collected at the first outpatient visit (mean age of 16.8 days and standard deviation of 8 days). No clinical condition compatible with congenital infection at birth was reported. A change in HC characterized by macrocephaly and mild global delay development was observed in a 1-year-old child whose mother was infected in the peripartum, but with normal TU. Changes in the TU were observed in 2 other children with nonspecific subependymal cystic malformation that was not evident by the cranial computed tomography. The other children monitored showed normal results in the Denver II test, in the HC and TU. No changes were identified on ocular ophthalmoscopy or auditory brainstem response test. Two children had an increase in serum ferritin levels during the first year of life, with the others' inflammatory disease markers normal.

Our study added knowledge about the neurodevelopment of children exposed to CHIKV during pregnancy by a longitudinal and prospective follow-up, throughout their first 24 months of life. We did not observe a negative impact of exposure to the virus on the neurological examination, global developmental test or measurements of the HC of these children.