Ten-year-old Elison nurses his 2-month-old brother Jose Wesley, who was born with microcephaly, at their house in Poco Fundo, Pernambuco state, Brazil. Felipe Dana / AP On Friday, the Centers for Disease Control and Prevention issued a travel alert for Mexico, Central America, South America, and the Caribbean, due to the outbreak of Zika virus in these regions and its association with birth defects.