In 2015 a sudden increase in the number of reported cases of microcephaly was reported in Brazil. At present, many sources suggest a connection between these cases and infection with the Zika virus. Although there have been several published case reports in which the Zika virus was found in affected women and their fetuses and newborns, the methodology used in diagnosis of many such cases is in doubt. The causal link between Zika infection and fetal anomaly has not been definitely, or even convincingly, demonstrated to date. The global campaign, aimed at improving the diagnosis, prevention, and possible treatment of Zika infection, was initiated on insubstantial evidence. Well-designed studies, and not just case reports, will be necessary to confirm and demonstrate the actual link between maternal infection and fetal anomaly. Likewise, the exact risk of vertical transmission and its fetal effects must be conclusively demonstrated. That there is a threat posed to the fetus by maternal Zika infection is certainly a possibility, but while there is so little real evidence, coincidence or too-rapid jumping to conclusions might be equally at work.