Microcephaly in Colombia before the Zika outbreak: A systematic literature review

Introduction: Microcephaly is characterized by a smaller than normal head circumference. Recently, Zika virus (ZV) has been associated with microcephaly. Objective: To describe the prevalence of microcephaly in Colombia taking as the baseline the information from the period before the Zika virus infection epidemics. Materials and methods: We reviewed Medline, Scopus, Scielo, Lilacs and annual reports of congenital malformation monitoring systems across Latin America, among others sources, for articles published before April, 2015, reporting the prevalence of microcephaly in Colombia between 1982 and 2013. Results: We identified 32 non-duplicate articles; we selected 25 articles for revision of which 12 met the criteria for inclusion in the systematic review, including 2,808,308 births. Conclusions: The prevalence of microcephaly in Colombia from 1982 to 2013, before the introduction of ZV, ranged from 0.3 to 3.1 per 10,000 births, with an average of 1.8 (95% CI 1.7- 1.8) per 10,000 births. These findings are important to determine if the prevalence after the introduction of the Zika virus infection registered significant changes.