Malaria and loaisis among blood donors at Ibadan, Nigeria.

115 blood donors were screened for the presence of malaria and other blood parasites at the Blood Bank, University College Hospital, Ibadan, between January and July, 1984. 11.3% of these had blood parasites; 7.8% had Plasmodium falciparum with parasitaemias from 0.03-0.2%, and 3.5% had Loa loa microfilaraemia. No other blood parasites were observed. Serological examination by the indirect fluorescent antibody test revealed that 86% of the donors had malaria antibody with reciprocal titres ranging from 16 to 512. There was no significant association between ABO blood group and malaria parasitaemia or antibody titre.