Abstract
BACKGROUND:
Plasmodium knowlesi is a zoonotic parasite that causes malaria in humans. The pathogen has a natural host reservoir in certain macaque species and is transmitted to humans via mosquitoes of the Anopheles leucosphyrus Group. The risk of human P. knowlesi infection varies across Southeast Asia and is dependent upon environmental factors. Understanding this geographic variation in risk is important both for enabling appropriate diagnosis and treatment of the disease and for improving the planning and evaluation of malaria elimination. However, the data available on P. knowlesi occurrence are biased towards regions with greater surveillance and sampling effort. Predicting the spatial variation in risk of P. knowlesi malaria requires methods that can both incorporate environmental risk factors and account for spatial bias in detection.
METHODS & RESULTS: We extend and apply an environmental niche modelling framework as implemented by a previous mapping study of P. knowlesi transmission risk which included data up to 2015. We reviewed the literature from October 2015 through to March 2020 and identified 264 new records of P. knowlesi, with a total of 524 occurrences included in the current study following consolidation with the 2015 study. The modelling framework used in the 2015 study was extended, with changes including the addition of new covariates to capture the effect of deforestation and urbanisation on P. knowlesi transmission.
DISCUSSION: Our map of P. knowlesi relative transmission suitability estimates that the risk posed by the pathogen is highest in Malaysia and Indonesia, with localised areas of high risk also predicted in the Greater Mekong Subregion, The Philippines and Northeast India. These results highlight areas of priority for P. knowlesi surveillance and prospective sampling to address the challenge the disease poses to malaria elimination planning.
| Original language | English |
|---|---|
| Article number | e0011570 |
| Pages (from-to) | 1-20 |
| Number of pages | 20 |
| Journal | PLoS Neglected Tropical Diseases |
| Volume | 18 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - 1 Jan 2024 |
Bibliographical note
Funding Information:This study was supported through funding provided by the Australian Centre for International Agricultural Research (ACIAR), as part of the ‘Evaluating zoonotic malaria transmission and agricultural and forestry land use in Indonesia’ (ZOOMAL) project (LS/2019/116, www.aciar.gov.au). Further support for this project was provided by the National Health and Medical Research Council of Australia through its Centres of Research Excellence (ACREME, GNT1134989 www.nhmrc.gov.au). FMS was supported by the National Health and Medical Research Council of Australia Investigator Grant Scheme (Emerging Leader Fellowship, 2021/GNT2010051 www. nhmrc.gov.au). JAF was supported by the Australian Research Council (ARC, FT210100034 and DP200100747 www.arc.gov.au). LEH was supported by a Melbourne Research Scholarship from the University of Melbourne (www.unimelb. edu.au). MJG was supported by the National Health and Medical Research Council of Australia Investigator Grant Scheme (Emerging Leader 2 Fellowship, 2023/GNT2017436 www.nhmrc.gov. au). GSR and MJG were supported by the National Institutes of Health, USA (R01AI160457-01 www. nih.gov). GSR was also supported by the Malaysian Ministry of Health (Grant Number BP00500/117/1002 www.moh.gov.my). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. This research was supported by The University of Melbourne’s Research Computing Services and the Petascale Campus Initiative (www.unimelb.edu.au). We thank Dr Timothy William for their support. We would like to also thank the Director General of Health Malaysia for the permission to publish this article.
Publisher Copyright:
© 2024 Tobin et al.
