View clinical trials related to Malaria Diagnosis.
Filter by:National malaria control strategies in pregnant women relies primarily on effective case management along with the use of long lasting insecticide-treated nets (LLINs)throughout pregnancy and intermittent preventive treatment with sulfadoxine-pyrimethamine (IPTp-SP) in the second and third trimesters in malaria-endemic regions in sub-Saharan Africa (SSA). For the latter, 3 or more doses are recommended by the national malaria control program (NMCP) but available data suggests that only 19% of eligible women received this in 2016 despite observed high attendance to antenatal clinic (ANC). Adherence to IPTp may be affected by perceptions, acceptability and contextual factors that need to be understood and therefore improve the effectiveness of this health interventions. In addition, all malaria cases should be confirmed either by microscopy or using a rapid diagnostic test (RDTs) before any treatment. Despite the crucial role of RDTs in improving malaria case management SSA, many malaria cases are missed in pregnant women due to the power performance of recommended RDTs which are unable to detect very low parasitaemia. Identifying lower density infections in pregnant women by the use of highly-sensitive RDTs and clearing them with an effective ACT could improve the outcome of the pregnancy in addition to IPTp-SP.
Investigators will evaluate approaches using magnetic bead capture, isolation, and surface tension valve transfer of biomarkers to process capillary blood in order to improve the sensitivity of already approved Rapid Diagnostic Tests (RDTs) for detection of human malaria infection. Results will be compared to those obtained using unenhanced capillary blood specimens directly applied to approved malaria RDTs. Participants seeking care for possible malaria in Zambia will be recruited to enroll in the study.
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 opportunities for exploring molecular tools for malaria diagnosis in endemic countries. With the objective of facilitating use of molecular tools for malaria control programs, the malaria laboratory at the Centers for Disease Control and Prevention (CDC) in Atlanta, USA developed a simple isothermal molecular method called Real-Time Fluorescence Loop-Mediated Isothermal Amplification (RealAmp) for the diagnosis of malaria. Currently, RealAmp primers exist for detecting the Plasmodium genus and the detection of P. falciparum and P. vivax species. The RealAmp method has great potential as a molecular tool for the diagnosis of malaria in the field (and other infections of major public health impact, such as HIV and tuberculosis). It can provide an alternative to conventional PCR-based diagnostic methods for field use in clinical and operational programs. The objective of this proposal is to validate the sensitivity of RealAmp for detection of malaria parasites in blood spots from patients with clinical diagnosis of malaria in two endemic states of Brazil with co-circulation of P. falciparum and P. vivax. In this evaluation, RealAmp and microscopic examination will be compared to a real-time PCR method as a reference test.