Vital Signs: Zika-Associated Birth Defects and Neurodevelopmental Abnormalities Possibly Associated with Congenital Zika Virus Infection - U.S. Territories and Freely Associated States, 2018

Abstract

Introduction: Zika virus infection during pregnancy causes serious birth defects and might be associated with neurodevelopmental abnormalities in children. Early identification of and intervention for neurodevelopmental problems can improve cognitive, social, and behavioral functioning.

Methods: Pregnancies with laboratory evidence of confirmed or possible Zika virus infection and infants resulting from these pregnancies are included in the U.S. Zika Pregnancy and Infant Registry (USZPIR) and followed through active surveillance methods. This report includes data on children aged ≥1 year born in U.S. territories and freely associated states. Receipt of reported follow-up care was assessed, and data were reviewed to identify Zika-associated birth defects and neurodevelopmental abnormalities possibly associated with congenital Zika virus infection.

Results: Among 1,450 children of mothers with laboratory evidence of confirmed or possible Zika virus infection during pregnancy and with reported follow-up care, 76% had developmental screening or evaluation, 60% had postnatal neuroimaging, 48% had automated auditory brainstem response-based hearing screen or evaluation, and 36% had an ophthalmologic evaluation. Among evaluated children, 6% had at least one Zika-associated birth defect identified, 9% had at least one neurodevelopmental abnormality possibly associated with congenital Zika virus infection identified, and 1% had both.

Conclusion: One in seven evaluated children had a Zika-associated birth defect, a neurodevelopmental abnormality possibly associated with congenital Zika virus infection, or both reported to the USZPIR. Given that most children did not have evidence of all recommended evaluations, additional anomalies might not have been identified. Careful monitoring and evaluation of children born to mothers with evidence of Zika virus infection during pregnancy is essential for ensuring early detection of possible disabilities and early referral to intervention services.

FIGURE 1

Children born to mothers with laboratory evidence of confirmed or possible Zika virus infection during pregnancy — U.S. Zika Pregnancy and Infant Registry, U.S. territories and freely associated states, February 1, 2017–June 1, 2018*^,†,§,¶,** * Percentages might not sum to 100 because of rounding. ^† Date and location of pregnancy completion were required to document a completed pregnancy in U.S. territories and freely associated states. ^§ Live-born infants include 4,199 infants from 4,165 pregnancies (includes 34 multiple gestation pregnancies). ^¶ Of the 691 children with no reported follow-up care as of June 1, 2018, 99 were reported to have moved out of U.S. territories and freely associated states. ** Of the 1,450 children aged ≥1 year by February 1, 2018, with some reported follow-up care by June 1, 2018, 154 were reported to have moved out of U.S. territories and freely associated states.

FIGURE 2

Percentage of children aged ≥1 year born to mothers with laboratory evidence of confirmed or possible Zika virus infection during pregnancy reported to have received recommended clinical evaluations*^,†,§,¶,** among children with reported follow-up care†† (n = 1,450) — U.S. Zika Pregnancy and Infant Registry (USZPIR), U.S. territories and freely associated states, February 1, 2017–June 1, 2018 Abbreviation: ABR = auditory brainstem response. * Physical examination after birth denotes at least one physical examination, indicated by length/height, weight, or head circumference measurements and date of measurements, at age >14 days reported to the USZPIR. ^† Developmental screening or evaluation denotes at least one developmental screening or evaluation result at age >14 days reported to the USZPIR. ^§ Neuroimaging denotes at least one postnatal imaging of the infant head (cranial ultrasound, computed tomography, or magnetic resonance imaging) result reported to the USZPIR. ^¶ ABR-based hearing screening or evaluation denotes at least one ABR-based hearing screen or evaluation result reported to the USZPIR. Of 1,450 children with reported follow-up care, 96% had at least one hearing screen or evaluation of any kind reported to the USZPIR. ** Ophthalmological evaluation denotes at least one ophthalmological evaluation result reported to the USZPIR. ^†† Any clinical care at age >14 days reported to the USZPIR.