Keywords:

Zika Congenital Infection, Zika Exposed Children School Performance, Strengths and Difficulties Questionnaire

Background:

Zika virus (ZIKV) is a mosquito-borne flavivirus responsible for Congenital Zika Virus Syndrome. There is limited data on long-term outcomes in school aged children without microcephaly with antenatal ZIKV exposure.

Objective:

To assess academic, social, behavioral, and emotional outcomes among normocephalic school-aged children with a history of antenatal ZIKV exposure and unexposed peers.

Methods:

We assessed academic performance and delivered the Strength and Difficulties Questionnaire (SDQ) to children with laboratory-confirmed ZIKV-antenatal exposure and non-exposed controls of the same age in Rio de Janeiro, Brazil. Clinical/demographic data were abstracted from medical charts and family interviews. Differences in results between cases and controls were assessed through Student’s T-test and chi-square. For cases, additional associations with timing of maternal ZIKV infection, neuro-sensory deficits and neurodevelopment were explored.

Results:

The study was conducted between February to April 2025. Data was obtained for 137 children: 77 with confirmed antenatal ZIKV, and 60 controls. Zika and Control groups had a mean age of 8.2 (range: 7-9) and 7.9 (range: 5-13) respectively, and similar distribution of attendance to public or private schools (p=0.6595). Reading, writing, and math difficulties were respectively 4.4 times (22.1% vs 5.0%), 4.2 times (20.8% vs 5%), and 4 times (14.3% vs 3.3%) more common in cases as compared to controls. Cases showed higher mean scores for total difficulties (13.38 vs 9.97, p=0.01), emotional symptoms (4.34 vs 2.98, p=0.0034) and hyperactivity (5 vs 3.17, p=0.001). Conduct difficulties, peer-related problems, and prosocial behavior scores were similar between groups. Logistic regression analysis of predictors of academic performance, distinct difficulty parameters and ZIKV-specific parameters is in progress.

Conclusions:

Our preliminary findings indicate increased academic challenges and daily difficulties in normocephalic children with antenatal ZIKV exposure as compared to controls. These results underscore the importance of long-term follow-up for all children exposed to maternal ZIKV during pregnancy to facilitate early identification and interventions for academic and social-behavioral concerns.