Evidence that Microcephaly Risk is Highest among Pregnant Women Infected Early in Pregnancy

Colombia has experienced a 4-fold increase overall in microcephaly following the Zika virus outbreak in 2016, according to a study published today in the CDC’s Morbidity and Mortality Weekly Report. This preliminary report on Zika virus disease and microcephaly in Colombia demonstrates that an increase in microcephaly is not specific to Brazil. This finding confirms that countries with Zika virus outbreaks are likely to experience large increases in microcephaly and other Zika-related birth defects. The report also suggests that Zika virus infection in the first months of pregnancy poses the greatest risk of microcephaly. More