Epidemiological Surveillance of Genetically Determined Microcephaly in Latin America: A Narrative Review

Background/Objectives: Congenital microcephaly is a clinical manifestation with a heterogeneous etiology, and its epidemiological surveillance relies on the systematic identification of cases and investigation of their underlying causes to inform preventive strategies and improve prognostic assessments. In Latin America, despite the existence of congenital anomaly reporting programs since 1967, the surveillance of microcephaly only gained substantial attention following the Zika virus (ZIKV) epidemic in 2015. Since then, efforts have predominantly concentrated on cases of infectious origin, often at the expense of recognizing endogenous etiologies, particularly those of genetic nature. This review aims to examine the role of genetic alterations in microcephaly pathogenesis and evaluates the limitations of current surveillance systems. Methods: A literature review centered on syndromic and non-syndromic genetic etiologies, alongside an analysis of Latin American surveillance frameworks (ECLAMC, RyVEMCE, ICBDSR, ReLAMC) was performed. Results: The findings reveal improved case detection and increased reported prevalence; however, the proportion of genetically attributed cases has remained stable. No systematic studies were found identifying the most common genetic causes; instead, genetic investigations were limited to isolated cases with a family history. Conclusions: While epidemiological surveillance systems in Latin America have advanced in the reporting of congenital microcephaly cases, substantial gaps remain in case ascertainment and etiological investigation, particularly concerning genetic contributions.