SummaryBackground The microcephaly epidemic, which started in Brazil in 2015, was declared a Public Health Emergency of International Concern by WHO in 2016. We report the preliminary results of a case-control study investigating the association between microcephaly and Zika virus infection during pregnancy.

Brazilian Ministry of Health, Pan American Health Organization, and Enhancing Research Activity in Epidemic Situations.

Affected nations need to prepare to provide complex and costly multidisciplinary care that children diagnosed with this new congenital syndrome will require.