Association between Congenital Zika Syndrome and hospitalizations during early childhood: a nationwide cohort study

•We evaluated almost 2,000 children with confirmed or probable CZS and 2.6 million without CZS.•We estimated hospitalization rates, causes, and length of stay for CZS and non-CZS•Rates of hospitalization were 3 to 7 times higher among CZS vs. non-CZS.•Increased morbidity in CZS children persisted during the first four years of life. Background Congenital Zika Syndrome (CZS) has been linked to a wide spectrum of abnormalities. However, differences in hospitalization patterns between children with and without CZS have not yet been investigated. Methods We compared rates of hospital admissions for all and specific diseases, proportions of admission causes, and total length of hospital stay (LOS) between children with CZS and those without the syndrome. Adjusted incidence rate ratios (aIRR) and aLOS were estimated using negative binomial regression. Results Compared to those without CZS, the aIRR for all-cause hospitalizations in the CZS group ranged from 3.77 (95%CI: 3.47–4.06) in the neonatal period to 7.76 (95%CI:6.91–8.61) at ages 2-4 years. Similar trends were observed for specific causes of admissions. Most admissions in the CZS group related to congenital malformations, neurological, respiratory and infectious diseases. aLOS ranged from 16.0 days[95%CI:13.2–19.5] to 19.9 days among CZS patients and 6.0 days[95%CI:5.9–6.2] to 9.3 days[95%CI:9.3–9.4] for patients without the syndrome. Conclusions Children born with CZS face significantly higher rates of hospitalization and longer stays compared to those without the syndrome during early childhood.