An outbreak of a little known virus called the Zika virus has caused women infected during pregnancy to give birth to infants with microcephaly, a condition marked by an abnormally small head, mental retardation, and growth and developmental abnormalities. The outbreak is predominantly occurring in Brazil, where the Brazilian Health Ministry recently reported 3,530 cases of microcephaly and 46 infant deaths possibly linked to the virus. In 2015 at least 2,782 cases of microcephaly were reported compared to 147 in 2014. The number of cases is increasing daily, and the peak mosquito season is in April, bringing fears that the