Seasonal characteristics of malaria infection in under-five children of a rural community in southern Ghana.

In a quarterly survey of malaria infection in the under-five children conducted at Gomoa Onyadze/Otsew Jukwa, a rural community in the Central Region of Ghana from December, 1986 to September, 1987, crude parasite rates ranged from 19.6 to 33.5 per cent in the dry season (December and March) and 33.0 to 44.0 per cent in the wet season (June and September). P. falciparum was the predominant parasite species by parasite formula analysis with higher rates in the rainy season (94.2 to 95.8 per cent) compared to that of the dry season (51.4 to 78.8 per cent). P. malariae (20.4 per cent), P. ovale (2.7 per cent) and mixed infection rates were higher in the dry season (December and March). As high as 30.4 to 44.8 per cent of positive parasite slides had parasite density of above 3200 per microliter of blood (above class 6 degree of parasitaemia). Depending on the season 7.2-27.3 per cent of children had parasite density above 25,600 per microliter of blood (above class 10 degree of parasitaemia).