OBJECTIVE: To assess malaria prevalence rates and seasonal patterns among clinically diagnosed malaria cases at the level of primary care facilities in an urban Sahelian setting. METHOD: Screening all patients consulting two private and two governmental providers on a randomly selected weekday over a period of 9 months. Patients with presumptive malaria underwent a blood test. RESULTS: Of 1658 patients included in the survey, 47% were clinically diagnosed and treated as malaria cases. Malaria was more often diagnosed by private providers. There were no clear seasonal patterns in presumptive malaria. A 30% of clinically diagnosed cases were positive for Plasmodium (all falciparum) by thick film examination. Thus, false positive cases constituted more than 70% of the clinically diagnosed malaria cases. The highest positive prevalence rates were found at the end and shortly after the rainy season (44%-47%) and the lowest during the dry season (2%). CONCLUSIONS: Clinical diagnosis of malaria has a very low positive predicted value in this low endemicity urban setting, and its low specificity leads to inappropriate care for a large proportion of patients. This has a major impact on economic costs for health services and households. In the Sahel, systematic use of microscopy-based diagnosis and/or rapid diagnostic tests should be considered to appropriately manage malaria and non-malaria cases.
OBJECTIVE: To assess malaria prevalence rates and seasonal patterns among clinically diagnosed malaria cases at the level of primary care facilities in an urban Sahelian setting. METHOD: Screening all patients consulting two private and two governmental providers on a randomly selected weekday over a period of 9 months. Patients with presumptive malaria underwent a blood test. RESULTS: Of 1658 patients included in the survey, 47% were clinically diagnosed and treated as malaria cases. Malaria was more often diagnosed by private providers. There were no clear seasonal patterns in presumptive malaria. A 30% of clinically diagnosed cases were positive for Plasmodium (all falciparum) by thick film examination. Thus, false positive cases constituted more than 70% of the clinically diagnosed malaria cases. The highest positive prevalence rates were found at the end and shortly after the rainy season (44%-47%) and the lowest during the dry season (2%). CONCLUSIONS: Clinical diagnosis of malaria has a very low positive predicted value in this low endemicity urban setting, and its low specificity leads to inappropriate care for a large proportion of patients. This has a major impact on economic costs for health services and households. In the Sahel, systematic use of microscopy-based diagnosis and/or rapid diagnostic tests should be considered to appropriately manage malaria and non-malaria cases.
Authors: Daniel T R Minja; Christentze Schmiegelow; Mayke Oesterholt; Pamela A Magistrado; Stéphanie Boström; Davis John; Caroline Pehrson; Daniel Andersen; Philippe Deloron; Ali Salanti; Martha Lemnge; Adrian J F Luty; Michael Alifrangis; Thor Theander; John P A Lusingu Journal: Malar J Date: 2012-06-21 Impact factor: 2.979