No evidence of sustained nonzoonotic Plasmodium knowlesi transmission in Malaysia from modelling malaria case data

Fornace, K. M. et al. (2023) No evidence of sustained nonzoonotic Plasmodium knowlesi transmission in Malaysia from modelling malaria case data. Nature Communications, 14, 2945. (doi: 10.1038/s41467-023-38476-8) (PMID:37263994) (PMCID:PMC10235043)

Abstract

Reported incidence of the zoonotic malaria Plasmodium knowlesi has markedly increased across Southeast Asia and threatens malaria elimination. Nonzoonotic transmission of P. knowlesi has been experimentally demonstrated, but it remains unknown whether nonzoonotic transmission is contributing to increases in P. knowlesi cases. Here, we adapt model-based inference methods to estimate RC, individual case reproductive numbers, for P. knowlesi, P. falciparum and P. vivax human cases in Malaysia from 2012–2020 (n = 32,635). Best fitting models for P. knowlesi showed subcritical transmission (RC < 1) consistent with a large reservoir of unobserved infection sources, indicating P. knowlesi remains a primarily zoonotic infection. In contrast, sustained transmission (RC > 1) was estimated historically for P. falciparum and P. vivax, with declines in RC estimates observed over time consistent with local elimination. Together, this suggests sustained nonzoonotic P. knowlesi transmission is highly unlikely and that new approaches are urgently needed to control spillover risks.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Fornace, Dr Kimberly
• Authors: Fornace, K. M., Topazian, H. M., Routledge, I., Asyraf, S., Jelip, J., Lindblade, K. A., Jeffree, M. S., Ruiz Cuenca, P., Bhatt, S., Ahmed, K., Ghani, A. C., and Drakeley, C.
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Nature Communications
• Publisher: Nature Research
• ISSN: 2041-1723
• ISSN (Online): 2041-1723
• Copyright Holders: Copyright © 2023 The Authors
• First Published: First published in Nature Communications 14: 2945
• Publisher Policy: Reproduced under a Creative Commons License

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
310866		Socio-ecological dynamics of zoonotic and vector-borne diseases in changing landscapes: implications for surveillance and control	Kimberly Fornace	Wellcome Trust (WELLCOTR)	221963/Z/20/Z	Institute of Biodiversity, Animal Health and Comparative Medicine