A clinical algorithm for the diagnosis of malaria: results of an evaluation in an area of low endemicity

We conducted a study of 1945 children and 2885 adults who presented with fe ver to a hospital outpatients clinic in an urban area of India order to dev elop and evaluate a clinical algorithm for the diagnosis of malaria. Only 1 39 (7%) children and 349 (12%) adults had microscopically confirmed malaria . None of the symptoms or signs elicited from the respondents were good pre dictors of clinical malaria. Simple scores were derived through combining c linical features which were associated with slide positivity or were judged by clinicians to be important. The best-performing algorithms were a score of 4 clinical features in children (sensitivity 60.0% and specificity 61.2 %) and a score of 5 in adults (sensitivity 54.6% and specificity 57.5%). Th e clinical features differed and algorithm performances were poorer than in previous studies in highly endemic areas. The conclusion is that malaria d iagnosis in areas of low endemicity requires microscopy to be accurate.