Abstract
Plasmodium knowlesi is the major cause of zoonotic malaria in Southeast Asia. Rapid and accurate diagnosis enables effective clinical management. A novel malaria diagnostic tool, Gazelle (Hemex Health, USA) detects haemozoin, a by-product of haem metabolism found in all Plasmodium infections. A pilot phase refined the Gazelle haemozoin identification algorithm, with the algorithm then tested against reference PCR in a larger cohort of patients with P. knowlesi mono-infections and febrile malaria-negative controls. Limit-of-detection analysis was conducted on a subset of P. knowlesi samples serially diluted with non-infected whole blood. The pilot phase of 40 P. knowlesi samples demonstrated 92.5% test sensitivity. P. knowlesi-infected patients (n = 203) and febrile controls (n = 44) were subsequently enrolled. Sensitivity and specificity of the Gazelle against reference PCR were 94.6% (95% CI 90.5–97.3%) and 100% (95% CI 92.0–100%) respectively. Positive and negative predictive values were 100% and 98.8%, respectively. In those tested before antimalarial treatment (n = 143), test sensitivity was 96.5% (95% CI 92.0–98.9%). Sensitivity for samples with ≤ 200 parasites/µL (n = 26) was 84.6% (95% CI 65.1–95.6%), with the lowest parasitaemia detected at 18/µL. Limit-of-detection (n = 20) was 33 parasites/µL (95% CI 16–65%). The Gazelle device has the potential for rapid, sensitive detection of P. knowlesi infections in endemic areas.
| Original language | English |
|---|---|
| Article number | 4760 |
| Pages (from-to) | 1-11 |
| Number of pages | 11 |
| Journal | Scientific Reports |
| Volume | 13 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - Dec 2023 |
Bibliographical note
Funding Information:The authors thank the study participants, the IDSKKS malaria research team (Maizatul Farina binti Abd Mutalib, Noorazela binti Mohamed Yassin, Mohd Rizan Osman, Danshy Alaza, and Azielia Elastiqah), Ranau District Hospital director and clinical/laboratory staff, Dr. Fiona Bizini of Ranau Public Health District (PKD Ranau), Dr. Dyang Ruksuna Md Ruhul, Dr. Wan Mohamad Haziman Bin Wan Taib and Dr. Mohd Fakhrurizal Bin Matdiris as well as the Sabah State Public Health Laboratory. They would like to thank the Director General of Health Malaysia for the permission to publish this article. This work was supported by the Australian Centre of Research Excellence in Malaria Elimination, the National Health and Medical Research Council, Australia (Grant Numbers 1037304 and 1045156, fellowships to NMA [1042072], MJG [1138860]), the National Institutes of Health, USA (R01AI160457-01) and Malaysian Ministry of Health (Grant Number BP00500/117/1002) awarded to GSR. SK is supported by a Menzies Future Leaders Fellowship. AFT is supported via a Malaysia Australia Colombo Plan Commemoration (MACC) and Australian Government Research Training Program (RTP) Scholarship at Charles Darwin University. MJG is supported by the Australian Centre for International Agricultural Research, and Indo-Pacific Centre for Health Security, DFAT, Australian Government (LS-2019-116).
Funding Information:
The authors thank the study participants, the IDSKKS malaria research team (Maizatul Farina binti Abd Mutalib, Noorazela binti Mohamed Yassin, Mohd Rizan Osman, Danshy Alaza, and Azielia Elastiqah), Ranau District Hospital director and clinical/laboratory staff, Dr. Fiona Bizini of Ranau Public Health District (PKD Ranau), Dr. Dyang Ruksuna Md Ruhul, Dr. Wan Mohamad Haziman Bin Wan Taib and Dr. Mohd Fakhrurizal Bin Matdiris as well as the Sabah State Public Health Laboratory. They would like to thank the Director General of Health Malaysia for the permission to publish this article. This work was supported by the Australian Centre of Research Excellence in Malaria Elimination, the National Health and Medical Research Council, Australia (Grant Numbers 1037304 and 1045156, fellowships to NMA [1042072], MJG [1138860]), the National Institutes of Health, USA (R01AI160457-01) and Malaysian Ministry of Health (Grant Number BP00500/117/1002) awarded to GSR. SK is supported by a Menzies Future Leaders Fellowship. AFT is supported via a Malaysia Australia Colombo Plan Commemoration (MACC) and Australian Government Research Training Program (RTP) Scholarship at Charles Darwin University. MJG is supported by the Australian Centre for International Agricultural Research, and Indo-Pacific Centre for Health Security, DFAT, Australian Government (LS-2019-116).
Publisher Copyright:
© 2023, The Author(s).
