Comparision of the various routine diagnostic modalities of malaria and a new method: the Parasight™ platform

Malaria is one of most important parasitic disease, which is still much prevalent in India. The burden of malaria in India is complex and the proportions of Plasmodium vivax and Plasmodium falciparum vary across India, because of the highly variable malaria eco-epidemiological profiles, transmission factors, and the presence of multiple Plasmodium species and Anopheles vectors. The diagnostic modalities which were being used currently, are at the risk of missing potential malaria cases, if a single test is being used for a given sample. There are some extremely sensitive and specific diagnostic methods available (e.g. PCR, LAMP), but they are expensive, complex, and not readily available in all healthcare setups. Therefore, this study aimed to compare three different types of routinely used diagnostic methods and a novel testing method, the Parasight™ platform, and compare them with the detection ability of the most accurate diagnostic method, that is, PCR. A total of 111 consecutive malaria-positive (proven positive by PCR) patients were taken and tested by the immunochromatographic test or the rapid diagnostic test (RDT), thin and thick blood smears, quantitative buffy coat (QBC). In the last year of study period, 26 PCR positive samples were also taken up for the Parasight™ platform diagnostic test, along with the other routine tests. Among 111 PCR-positive cases, 78.4% samples were positive by Giemsa-stained blood film examination, 80.2% by QBC, 87.4% by RDT. In the last year of study period, among the 26 PCR-positive malaria samples, 80.8% were positive by blood film examination, 84.6% by QBC, 96.2% by RDT and 100% by the Parasight™ platform test. A combination of tests is preferable than a single method, for better detection of Plasmodium species including automated methods. The new testing method, the Parasight™ platform, is emerging to be a very sensitive test for detection of Plasmodium spp., results of which are comparable to PCR.