Challenges and lessons learned from the rapid operationalization of a prospective cohort to study the natural history and neurodevelopmental outcomes of postnatal Zika virus infection among infants and children in rural Guatemala.

During the course of the 2015-2017 outbreak of Zika virus (ZIKV) in the Americas, the emerging virus was recognized as a congenital infection that could damage the developing brain. As the Latin American ZIKV outbreak advanced, the scientific and public health community questioned if this newly recognized neurotropic flavivirus could affect the developing brain of infants and young children infected after birth. We report here the study design, methods and the challenges and lessons learned from the rapid operationalization of a prospective natural history cohort study aimed at evaluating the potential neurological and neurodevelopmental effects of postnatal ZIKV infection in infants and young children, which had become epidemic in Central America. This study enrolled a cohort of 500 mothers and their infants, along with nearly 400 children 1.5-3.5 years of age who were born during the initial phase of the ZIKV epidemic in a rural area of Guatemala. Our solutions and lessons learned while tackling real-life challenges may serve as a guide to other researchers carrying out studies of emerging infectious diseases of public health priority in resource-constrained settings.

Reliability and Validity of an Adapted and Translated Version of the Mullen Scales of Early Learning (AT-MSEL) in Rural Guatemala.

BACKGROUND: A growing literature base supports the use of tests developed in high-income countries to assess children in low resource settings when carefully translated, adapted, and applied. Evaluation of psychometric properties of adapted and translated measures within populations is necessary. The current project sought to evaluate the reliability and validity of an adapted and translated version of the Mullen Scales of Early Learning (AT-MSEL) in rural Guatelama. METHODS: The reliability and validity of the AT-MSEL in rural Guatemala were analyzed for children ages 0-5 years. RESULTS: Interrater reliability coefficients (ICC = 0.99-1.0) and internal consistency (Cronbach's alpha = 0.91-0.93) were excellent for all subscales. General linear models utilizing paired data showed consistency between standard scores (p < 0.0001). Mean raw scores increased with chronological age, as expected. Across age groups, subscales were significantly, positively correlated with one another (p < 0.05 - < 0.001) with one exception, visual reception and expressive language at the 0-10 month age range (p = 0.43). CONCLUSIONS: The AT- MSEL showed strong psychometric properties in a sample of young children in rural Guatemala. Findings demonstrate that the AT-MSEL can be used validly and reliably within this specific population of children. This work supports the concept that tests developed in high-income countries can be used to assess children in low resource settings when carefully translated, adapted and applied.