Speech-language disorders in children with congenital Zika virus syndrome: A systematic review

Introduction: Having verified the true association between the Zika virus and the occurrence of microcephaly, studies were conducted to evaluate the effects of the infection on fetal development. Congenital Zika virus syndrome is a currently known condition but little addressed regarding speech, language, and hearing disorders in children.

Objective: To conduct a systematic review of speech, language, and hearing disorders in children with congenital Zika virus syndrome.

Methods: This systematic review followed the PRISMA instructions and the Joanna Briggs Institute guidelines, and it was registered in PROSPERO (CRD42018111764). The databases consulted were Cochrane, SciELO, PubMed, LILACS, Scopus, Web of Science, and ScienceDirect. OpenGrey and OpenThesis were used to partially capture the "grey literature". Observational studies of children with microcephaly due to congenital Zika virus syndrome were included. The risk of bias was analyzed using the 2017 Joanna Briggs Institute.

Results: 707 records were obtained and, after excluding the duplicates, 644 studies remained. After applying the inclusion criteria, 24 articles were considered eligible. Children with congenital Zika virus syndrome presented abnormal persistence of primitive reflexes (94.7%), impaired cognitive development (95.1%), delayed neuropsychomotor development (between 92.8 and 100%), hypertonia (between 74.7% and 90.1%), impaired language development (between 68.42% and 100%), retrognathia (38.6%), craniofacial disproportion (between 32.9% and 95.8%), altered tongue frenulum (between 30% and 36.36%), the absence of stapedial reflexes (27.3%), dysphagia (between 14% and 88.9%), and hearing changes (between 5.8% and 68.42%).

Conclusion: Children with congenital Zika virus syndrome may have speech, language, and hearing disorders such as hearing loss, dysphagia, alteration in the tongue frenulum, and delays in neuropsychomotor and language development.