Abstract
A seroparasitological study of malaria was carried out in two of the more important islands of Equatorial Guinea, Bioko (ex Fernando Poo) and Annobón. The study involved a randomly-chosen population of children aged from two to nine years. In Bioko 1130 children were chosen from 29 of the 51 villages on the island; in Annobón 185 children were chosen from the capital town, where all the population lived. Indirect immunofluorescence tests (IFAT) showed a prevalence of malaria infection of 29·8% in Bioko and 55·7% in Annobón. The parasitic prevalence (malaria index) was 26·6% and 55·1% respectively, and the splenic index was 57·0% and 54·6% respectively. The results indicate that this is an area of stable hyperendemic malaria, which may benefit from an antimalarial programme.