Rapid Malaria Test Evaluated In Different Locales

A recently introduced malaria rapid diagnostic test (RDT) has been evaluated in an area endemic for the disease in Africa and in a nonendemic setting in Europe.

The RDTs are a useful tool in endemic malaria countries, where light microscopy is not feasible and in nonendemic countries where they can be used as complementary tests to provide timely results in case of microscopy inexperience.

Scientists at the Hospices Civils de Lyon (France) working with colleagues in Mali, tested blood samples that were collected during a 12-months and six-months period in 2011 from patients suspected to have malaria in Lyon and Bamako, respectively. Samples of 877 patients from both sites were included in the study.

The samples were examined by light microscopy, the VIKIA Malaria Ag Pf/Pan RDT (IMAccess; Lyon, France) and in Bamako additionally with the CareStart RDT (AccessBio, Somerset, NJ, USA). All discordant results between microscopy and the two RDTs were resolved by a real time polymerase chain reaction (PCR) and test characteristics were recalculated according to the PCR-corrected results. Sensitivity, specificity, positive predictive value, and negative predictive value were used to evaluate test performance.

The VIKIA Malaria Ag Pf/Pan RDT is an immunochromatographic test in which monoclonal antibodies target the histidine-rich protein II (HRP-II) protein antigen specific to Plasmodium falciparum and the Pan Aldolase antigen, common to all the Plasmodium species. This RDT had sensitivity for Plasmodium falciparum of 98% in Lyon and 96% in Bamako, and its performance was similar to PCR-corrected microscopy. No significant difference in the detection of falciparum and non-falciparum malaria between the two RDTs was observed. The performance of the VIKIA RDT was not significantly different for P. falciparum and non-falciparum species compared to PCR-corrected microscopy method.

The authors concluded that the VIKIA Malaria Ag Pf/Pan showed a similar level of performance to comparative RDTs in endemic and in nonendemic settings. Community health workers were as efficient as medical students in managing malaria cases using both RDTs tested. This RDT, which has recently become commercially available, could be used to implement efficient malaria diagnosis in low-income endemic countries or complement PCR/microscopy diagnosis in nonendemic regions. The study was published on June 6, 2013, in the Malaria Journal.

Related Links:
Hospices Civils de Lyon
IMAccess
AccessBio