Clinical algorithm for malaria during low and high transmission seasons.

OBJECTIVES: To assess the proportion of children with febrile disease who suffer from malaria and to identify clinical signs and symptoms that predict malaria during low and high transmission seasons. STUDY DESIGN: 2490 children aged 2 to 59 months presenting to a health centre in rural Ethiopia with fever had their history documented and the following investigations: clinical examination, diagnosis, haemoglobin measurement, and a blood smear for malaria parasites. Clinical findings were related to the presence of malaria parasitaemia. RESULTS: Malaria contributed to 5.9% of all febrile cases from January to April and to 30.3% during the rest of the year. Prediction of malaria was improved by simple combinations of a few signs and symptoms. Fever with a history of previous malarial attack or absence of cough or a finding of pallor gave a sensitivity of 83% in the high risk season and 75% in the low risk season, with corresponding specificities of 51% and 60%; fever with a previous malaria attack or pallor or splenomegaly had sensitivities of 80% and 69% and specificities of 65% and 81% in high and low risk settings, respectively. CONCLUSION: Better clinical definitions are possible for low malaria settings when microscopic examination cannot be done. Health workers should be trained to detect pallor and splenomegaly because these two signs improve the specificity for malaria.