"Zika is a virus that is primarily spread by Aedes mosquitoes--the same mosquitoes that transmit dengue, chikungunya, and yellow fever. Zika transmission has also been documented from mother to child during pregnancy, as well as through sexual intercourse, blood transfusions, and laboratory exposure. Scientists first identified the virus in 1947 among monkeys living in the Ugandan Zika forest. Five years later, human cases were detected in Uganda and Tanzania. The first human cases outside of Africa were diagnosed in the Pacific in 2007 and in Latin America in 2015. From January 1, 2007, to April 7, 2016, Zika has spread to 62 countries and territories, and the World Health Organization (WHO) expects the disease to spread to more countries where Aedes mosquitos reside. Scientists are also exploring whether other vectors can spread the disease."
CRS Insight, IN10433
Federation of American Scientists: http://www.fas.org/sgp/crs/index.html