Anaemia in mice with concomitant Schistosoma mansoni and Plasmodium berghei yoelii infection.

1. The effect on anaemia in mice given Plasmodium berghei yoelii 3 and 5 weeks after exposure to Schistosoma mansoni cercariae, was investigated. 2. Haematological criteria (PCV and haemoglobin levels), reticulocytosis, parasitaemia and splenomegaly were used as indices. 3. Anaemia was severe in the animals given P. b. yoelii and in those with mixed infection (P. b: yoelii plus S. mansoni). Malaria was found to dominate the picture until the clearance of the parasitaemia. The effect of the interaction between the diseases on the anaemia was nil. 4. Toward the end of the experiment, moderate splenomegaly was observed in the mice with mixed infection.