Brazil President Rousseff guarantees resources for Zika vaccine

Brazil's President Dilma Rousseff said her government would provide all resources needed to develop a vaccine against the Zika virus during a speech in the northeastern city of Petrolina on Friday.

Much remains unknown about Zika, including whether the virus actually causes microcephaly, a condition marked by unusually small heads that can result in developmental problems.

Brazil said it has confirmed more than 500 cases of microcephaly, many in the Northeast, and considers most of them to be related to Zika infections in the mothers. Brazil is investigating more than 3,900 additional suspected cases of microcephaly.