Symptomatic diagnosis of Plasmodium falciparum malaria in field conditions

This paper examines the relationship between clinical manifestations and parasitaemia in relation to malaria endemicity. Discriminant analysis, showed that fever alone can detect 74.4% of the parasite positive cases and the inclusion of other symptoms like headache, vomiting, nausea, bodyache and diarrhoea marginally increases the efficiency of discrimination (i.e., from 74.4% to 74.7%). It was observed that the association of symptoms with parasitaemia varies with the degree of malaria endemicity. The percentage of correct classification of parasite carriers varied from 45.7% in the immune population to 80.6% in the non-immune population. A significant difference was observed in the density grades between symptom positive and symptom negative cases. Slide examination in hyperendemic area does not give any advantage over the clinical examination and the data obtained from the slides collected during fever surveys tend to overestimate the malaria incidence in hyperendemic area.