Comparative study of blood smears microscopy and rapid test strips in accurate malaria diagnosis

Abstract

Swift diagnosis of Plasmodium falciparum remains a major problem to scientists and medical practitioners. Diagnostic tools based on the dipstick principle for the detection of plasmodium histidine rich protein 2 (HRP-2) antigens, specific parasite lactate dehydrogenase (PLDH), and antibodies of all isotypes specific for P. falciparum and P. vivax respectively have become available for the qualitative detection of malaria parasites. To evaluate two of the currently available assay methods, specimen from 200 patients admitted on provisional diagnosis of malaria were screened in this study and compared with the smear microscopy method. Our results showed a statistical significant difference (p< 0.05) between the two rapid strip methods of ACON and SD Bioline. There was also a significant statistical difference (p<0.05) between microcopy method and combined rapid test strip methods in the study. The health point prevalent rate of malaria in the study was 50% with a significant statistical difference (p<0.05) between routine macroscopic test results and research study results. A crude parasites survey of 2000 children in the city suburb showed a parasites rate of 30.8%. Malaria infected patients showed a health seeking behavior at a malaria intensity of 28 - 43 parasites per 100 WBCs in the study. While identification of blood forms of the parasites in blood smear microscopy remains the gold standard for malaria diagnosis, we recommend detailed evaluation and quality control of commercial test strips to avoid erroneous results.


IJONAS Vol. 3 (1) 2007: pp. 122-126