Review Article: Recent Advances in the Laboratory Diagnosis of Malaria

Abstract

Malaria is a global health problem with about 2-4 billion people at risk, about 200-300 million cases occurring annually resulting in about 1 million deaths, 90% of which occur in the sub-Saharan Africa. Prompt and accurate diagnosis is the key to effective disease management, one of the main interventions of the Global Malaria Control Strategy. The “gold standard” test for the diagnosis of malaria, blood film microscopy, has in recent times come under some criticism. Apart from being cumbersome and time consuming, the reliability of the test depends on the competence of the microscopist and the test is not sensitive when parasitaemia is less than 100 parasites/µL of blood, a situation usually seen in non-immune subjects. Several new innovative malaria diagnostic tests called Rapid Diagnostic Tests (RDT) have been developed to circumvent these limitations. The application of these new techniques in clinical laboratories is limited by cost, variable sensitivities, spill-over antigenaemia and false positive reactions in some cases. Although the polymerase chain reaction (PCR) assays for malaria diagnosis is extremely sensitive and specific, and has been suggested to replace blood film microscopy as the “gold standard”, the long time, high cost and technical expertise required is limiting the usefulness of these techniques, especially in Africa. This communication provides information on the available malaria diagnostics and the recent advances in the laboratory diagnosis of malaria.

Key words: Recent advances, malaria diagnostics

Afr. J. Clin. Exper. Microbiol. 2005; 6(2): 113-123