Dear Editors, The paper by van der Linden et al., “Discordant clinical outcomes of congenital Zika virus infection in twin pregnancies” provides additional information in a story that has placed Zika firmly in the company of other infections such as cytomegalovirus and toxoplasmosis that can cause birth defects in the central nervous system. Unlike these other congenital infections, however, Zika virus regularly causes a particularly severe brain phenotype, rarely seen even by specialists in brain malformations. While microcephaly, central nervous [...]