An epidemiological study of malaria in Bioko and Annobón islands (Equatorial Guinea).

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.