Implications of Zika Virus exposure during pregnancy for visual function development

Author(s)

Diego da Silva Lima

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Psicologia (IP/SBD)
• Defense date: 2019-06-04

Examining board members

Dora Selma Fix Ventura; Saulo Duarte Passos; Andrea Araujo Zin

• Advisor: Dora Selma Fix Ventura

Abstract

Congenital Zika Syndrome (CZS) is a developmental condition resulting from Zika Virus (ZIKV) maternal infection during pregnancy. This condition is characterized by microcephaly and a series of other neurological and ophthalmological outcomes. Chorioretinal atrophies, focal pigmentary mottling, strabismus and infection in vision-related central nervous system structures have all been identified in CZS patients or verified in experimental models. Due to the multiple ways in which ZIKV might impair visual function in early life, we studied this condition through the assessment of visual acuity (VA) longitudinally in a sample of infected children, irrespective of the presence of CZS symptoms. The present work aims to follow up the VA development of children infected by ZIKV during pregnancy and relate the potential CZS symptoms to any identified losses. Children in a Control Group (N=27), in a group in which confirmation of exposure came from a sample from the mother (ZE; N=22) and a group in which confirmation of exposure came from a sample from the child (ZI; N=11) had their VA measured via the Teller Acuity Cards (TAC) method on 2 to 4 occasions during the first 30 months of life. VA developed normally in patients that did not present CZS outcomes, with rare exceptions. In a sub-sample of the ZI group which presented clinical symptoms consistent with CZS, VA was within normative values, with the exception of one child that presented chorioretinal atrophies. The presence of ophthalmological outcomes seems to be predictive of visual function losses of high magnitude. In cases of ZIKV-infected children without symptoms or presenting only mild symptoms, VA seems to be developing normally. A more long-term follow up is suggested for such cases (AU)

• FAPESP's process: 16/24631-8 - Implications of Zika virus exposure during gestation for the development of visual function
• Grantee: Diego da Silva Lima
• Support Opportunities: Scholarships in Brazil - Master