Malaria diagnosis: a review

RESUMO

Malaria is the most prevalent endemic disease in large parts of the world and is subject to control by health authorities. Today, the goal of malaria control is to prevent mortality and reduce morbidity and socioeconomic losses through the progressive improvement and strengthening of local and national capabilities. The World Health Organization considers early diagnosis as the first basic element of the strategy to control the disease. Traditionally, laboratory diagnosis has been made using the thick blood film, which continues to be the gold standard test. However, this test has disadvantages such as the manner in which the film is prepared, the level of training of the observer, the adequacy of maintenance of materials and equipment and its only fair sensitivity. Thus, many research laboratories have concentrated their efforts on the development of alternative methods for malaria diagnosis. These include methods for the detection of Plasmodia within erythrocytes (fluorescent microscopy, Quantitative Buffy Coat (QBC(), dark field microscopy, nucleic acid probes and immunofluorescence), methods for the detection of plasmodial antigens in body fluids (radioimmunoassay, enzyme immunoassay) and methods for the detection of anti-plasmodial antibodies in serum (indirect immunofluorescence, enzyme immunoassay, Western blotting). Here, we critically review the various methods for malaria diagnosis based on the world's literature and our experience with most of them, with emphasis on recent advances.