Perinatal Mother-to-Child Chikungunya Virus Infection: Screening of Cognitive and Learning Difficulties in a Follow-Up Study of the Chimere Cohort on Reunion Island

Abstract

In this cohort study, we evaluated the cognitive and learning difficulties of school-age children perinatally infected with Chikungunya virus (CHIKV) on Reunion Island using the Evaluation of Cognitive Functions and Learning in Children (EDA) battery screening test compared to the healthy children cohort used for EDA development. Of the 19 infected children, 11 (57.9%) exhibited subnormal or abnormal scores, of whom 3 were classified as high risk, and 8 were classified as at risk for cognitive and learning difficulties. Children who had encephalopathy were at higher risk for displaying at least one difficulty than non-encephalopathic children (relative risk 2.13; 95% CI 1.05-4.33). The difficulties observed affected verbal functions, non-verbal functions, and learning abilities, such as phonology, lexical evocation and comprehension, graphism, selective visual attention, planning, visual-spatial reasoning, dictation and mathematics, as well as core executive functions, such as inhibitory control, shifting, and working memory. Neurocognitive dysfunctions could be linked to severe brain damage, as evidenced by severe white matter reduction mainly in the frontal lobes and corpus callosum and potentially in all functional networks involved in difficulties. These results should motivate further investigation of intellectual and adaptive functioning to diagnose intellectual deficiency and severe maladaptive behaviour in children perinatally infected with Chikungunya virus.

Keywords: Chikungunya virus; arbovirus; central nervous system; cognitive function; cohort study; congenital infection; encephalitis; encephalopathy; learning difficulties; neonate.

Figure 1

Study population.

Figure 2

EDA Z-scores. (A) Percentage of CHIKV-perinatally-infected children in the three risk categories based on Z-scores. (B) Mean Z-scores for each EDA subscale and disease presentation (encephalopathic vs. non-encephalopathic). A: Phonology, B: lexical evocation, C: lexical comprehension, D: syntactic expression, E: syntactic comprehension, F: graphism, G: selective visual attention, H: planning, I: visual–spatial reasoning, J: reading, K: dictation, L: mathematics.