Laboratory diagnosis of malaria

Malaria particularly falciparum malaria is a major public health problem in India. Its correct and early diagnosis is very important for prompt treatment as a preventive and control measure. Microscopy is the traditional method for laboratory diagnosis of malaria, which is used widely. However, it is time consuming, needs expertism and the detection limit is 10-20 parasites/ml blood in thick film and 100 parasites/ml blood in thin film. Quantitative buffy coat technique (QBC) is highly sensitive method but expensive equipment is needed for this test. The serological methods involving antibody detection give information regarding exposure to malaria but do not differentiate between present and past infections. Genetic probes and PCR are highly sensitive methods but require expensive equipments. Parasite antigen detection tests are useful in field and PHC level for rapid diagnosis of P falciparum malaria.LDH based test for diagnosing malaria is sensitive but can not differentiate between species. For monitoring of drug resistance or follow-up of patients, methods which can quantify parasitaemia are needed. Simply microscopy is the best solution at present.