Fischer P R
Department of Pediatrics, University of Utah, Salt Lake City 84132, USA.
J Parasitol. 1996 Aug;82(4):635-7.
Until recently, congenital malaria was thought to be rare. Now, several reports suggest that more than 10% of newborns in some settings are parasitemic. The pathophysiology of transplacental transmission of Plasmodium is not well understood, and no animal model of congenital malaria exists. A rodent model of malaria in pregnant females, however, has been developed. In an effort to test the usefulness of this model in the study of congenital malaria, Wistar rats were injected intraperitoneally with approximately 10(6) NYU-2 strain Plasmodium berghei-infected erythrocytes at various times relative to conception. Perinatal maternal and neonatal blood was tested for the presence of parasites. Two rats infected preconceptually, 1 at 29 and the other at 11 days prior to mating, delivered aparasitemic pups. Fourteen rats were inoculated during gestation. Five of 5 rats infected on the fifth gestational day succumbed prior to delivery; 1 fetus was parasitemic. Offspring of females infected on the 9th, 10th, 12th, and 14th days of gestation were aparasitemic at birth. Four rats conceived after an initial Plasmodium infection had waned and were reinfected during pregnancy; none of their pups showed evidence of parasitemia. Thus, though rare, transplacental passage of malaria parasites can occur in rats. The Wistar rat-P. berghei model of gestational malaria, however, does not seem to be useful for the study of congenital malaria.
