Concern over Zika virus outbreak: another alarming global threat Muhammad Yusuf Hafiz,1 Syed Uzair Mahmood,2 Maria Shoaib,1 Farah Hafiz Yusuf1 1Dow Medical College, Dow University of Health Sciences, 2Sindh Medical College, Jinnah Sindh Medical University, Karachi, Pakistan Abstract: Zika virus, as highlighted by the World Health Organization in February 2016, has emerged as a public health emergency of international concern. Zika virus is enveloped and icosahedral, and has a nonsegmented, single-stranded, positive-sense RNA genome. It belongs to Flaviviridae family. Aedes aegypticus mosquito is the known vector. Transmission is anthroponotic (human to vector to human) during outbreaks, or occurs perinatally in utero, sexually, and via transfusion of infected blood. Zika virus is turning out to be a major public health concern. Not only has it shown dramatic teratogenic association and caused serious neurological concerns but it has also spread around the globe. Countries that have not yet been affected by Zika virus should adopt proper preventive methods to limit its spread in the population. Keywords: Zika virus, global spread, teratogenic, neurological anomalies, public health emergency