[Congenital malaria in a twin].

Congenital malaria is rare even in endemic areas. It is even rarer in a single twin. When this was presented in a clinical case, the diagnosis was checked for the presence of Plasmodium vivax in peripheral smears and it was treated with chloroquine as the selected drug. The twin brother never presented clinical manifestations, either from the laboratory or the illness. We comment on the factors that facilitate transplacental transmission.