Glimpses from NIRTH Study Site Performance of a New Portable, Affordable Diagnostic Test to Detect Malaria Parasites in India Poster # 84 Session name: POS1 December 13th Bharti PK1, Thota P2, Kumar R1 , Witte T2, Rocheleau A2, Verma AK1, Rajasubramaniam S1, Kumar P3, Das A1 1ICMR-National Institute of Research in Tribal Health, Jabalpur, Madhya Pradesh India; 2Hemex Health, Inc; Portland, USA; 3Hemex Dx, India. Abstract Objective Results & Summary   RDT+ RDT- LM+ 42 LM- 17 203   Gazelle + Gazelle - LM+ 41 1 LM- 7 213 The objective of the study is to compare the performance of GazelleTM to current diagnostic methods in detecting malaria parasites. We evaluated the diagnostic accuracy of a rapid (<1 minute) malaria detection device, GazelleTMusing blood samples (n= 285) from a high transmission setting (Jagdalpur, India). GazelleTM uses the principle of Magneto-Optical Detection to detect hemozoin (a paramagnetic by-product of the malaria parasite). The accuracy of GazelleTM was compared with RDT and microscopy (gold standard). Results demonstrate that GazelleTM has similar sensitivity and a much higher specificity than RDTs and was much faster at one-minute than either microscopy or RDTs. To test the accuracy and compare the relative performance of GazelleTM vs. RDT using microscopy as the gold-standard Methods & Mechanism We evaluated the diagnostic accuracy of the GazelleTM as a point-of-care diagnostic for malaria, using samples collected from 300 patients who were enrolled in a pilot study in a high transmission setting (Jagdalpur-NIRTH, India). 262 patients were included in the analysis. 7 patients were excluded due to contamination and 31 were excluded due to damaged prototype device. Microscopy was performed as per WHO guidelines. Table 1: Comparison of methods of detecting malaria parasites (N=262) RDT-Rapid Diagnostic Test; LM-Light Microscopy Background The Magneto-Optical Detector (MOD) detects a byproduct of malaria infection in a drop of blood. When malaria parasites consume red blood cells, they create paramagnetic iron-containing crystals called hemozoin inside red blood cells   Sensitivity Specificity Accuracy Gazelle 97.6 96.8 97.0 RDT 100 92.3 93.5 Malaria is one of the most severe public health problems worldwide and is prevalent in tropical and subtropical regions. The mainstay of malaria diagnosis has been microscopic examination of blood and more recently rapid diagnostic tests (RDTs). Mechanism of hemozoin detection by MOD Magnified photos of hemozoin crystals – the biomarker detected by MOD Table 2: Effectiveness/accuracy of RDT and Gazelle for detecting Malaria parasites compared to Microscopy (Gold Standard). In the current study Gazelle performed similar to microscopy and has higher specificity than RDTs Gazelle showed 97.6% sensitivity and 96.8% specificity when compared to Microscopy On the same samples RDTs showed 100% sensitivity and 92.3% specificity Labor & time intensive (~30-60min) Skilled personnel Requires power Poor sensitivity and specificity for lower parasitemia Inter-operator error in creation, staining, and visual analysis False positives Variation in sensitivity across malaria species and variants 20 minutes per test and heat-sensitive Cannot detect P. falciparum with HRP2 deletion Cannot reliably detect parasitemia lower than 100-200 parasites/μL Testing procedure Conclusions 15 µl of whole blood collected with cartridge Snap into bottom chamber Insert cartridge into reader Results onscreen in under a minute Upload results to cloud with touch of a button This study shows promising early results for Gazelle with good sensitivity and specificity. Gazelle performed similarly to microscopy and has higher specificity than RDTs. Gazelle may be a potential solution for areas where there is need for speed, accuracy and ease of use (such as where microscopy is not practical and where RDTs’ poor specificity is an issue). Feedback from the field was that a one-minute, battery operated test is unique and useful. Next steps: Future studies are planned with larger numbers of subjects that compare results to PCR. Challenge: There is an acute need for improved malaria diagnostics that are not only cost-effective but also rapid, highly accurate and detect species and strains that other diagnostics may miss, such as low-density infection, and P. falciparum with HRP2 deletion. Glimpses from NIRTH Study Site Solution Gazelle: An inexpensive, rugged and rapid (<1 minute) malaria detection device. Portable Water and Heat Resistant Standalone test Battery powered Wi-Fi Bluetooth GPS Acknowledgments MOD technology was licensed from Case Western Reserve University, Cleveland, OH The Gazelle reader was developed by Hemex Health, USA & India in collaboration with Tata Elxsi, Pune, India The study was funded by Hemex Health Please contact info@hemexhealth.com and saprapbs@yahoo.co.in with any questions or suggestions For more information please visit www.HemexHealth.com. and www. nirth.res.in Note: This is a prototype unit and not approved for sale in India yet. Final device will include the ability to detect Sickle Cell Disease Most sensitive hemozoin detector available Studies on P. vivax yielded higher sensitivity and specificity when compared to RDT and microscopy.