Congenital malaria in Papua New Guinea

The incidence of malarial infection in pregnant women at delivery, their corresponding infants and umbilical cords and a control group of non-pregnant women were investigated in the Madang region of Papua New Guinea. Anti-malarial antibody titres were measured in maternal and paired cord sera. Parasitaemia occurred in 18/73 (24.7%) of non-pregnant females compared with 15/51 (29.4%) of pregnant females. Malarial parasites were found in 7/48 (14.6%) cord blood samples and in 4/52 (7.7%) samples of the infant's peripheral blood, indicating transplacental transmission. Infection with Plasmodium falciparum was commoner in pregnant than non-pregnant females, and accounted for all the cord and infant infections. A significant correlation was found between anti-malarial IgG antibodies in paired maternal and cord bloods. There was an association between umbilical cord infection and low levels of cord antibody. Clinical malaria developed in at least one out of the 7 cases in which placental transfer of parasites was known to have occurred. This study suggests that transfer of parasites across the placenta is a common event in Papua New Guinea. Further consideration should be given to treatment with anti-malarial drugs of infants with cord or peripheral blood parasitaemia or, indeed, of all infants of mothers with parasitaemia.