Validation of RealAmp Method for the Diagnosis of Malaria in Endemic Areas of Brazil

Worldwide, approximately 2 billion people live in areas at risk for malaria with morbidity surpassing 250 million cases, with approximately 800,000 deaths, per year. Of the four species of malaria parasites that cause human infection, P. falciparum is responsible for the majority of severe malaria cases followed by P. vivax. Early and accurate diagnosis is essential for prompt and correct treatment, which can reduce the death rate and interrupt transmission. Currently, conventional methods for the diagnosis of malaria include microscopic examination of thin and thick blood smears and rapid diagnostic tests (RDTs). Light microscopy in practice typically detects parasitemia as low as 100 parasites/µl and it can differentiate species. The advantage of microscopy includes the ability to estimate parasitemia, the possibility to identify parasite stages, including gametocytes, and its low cost. However, this method is labor intensive, difficult to standardize, and requires well-trained microscopists. The majority of RDTs are based on detection of P. falciparum histidine-rich protein 2 (HRP-2) antigen and do not detect all malaria species. RDTs that detect lactose dehydrogenase (LDH) and aldolase generally broadly react with all four species of malaria parasites and therefore cannot differentiate among the species although efforts are underway to improve their performance for species detection. In settings where multiple malaria species co-circulate, molecular methods may be more reliable than microscopy and RDTs in accurately diagnosing the species of malaria parasites with low parasitemias. However, conventional molecular methods, such as nested polymerase chain reaction (nested PCR) or real-time PCR, are technically challenging and resource intensive and are generally restricted to reference laboratories due to the need for well-equipped laboratories. Recently, new molecular methods that can be used in field settings have been developed and this opens up new opportuniti