Impact Of Arthemether Lumefantrine Treatment, Circadian Rhythm And Serum Replacement On The Mosquito Infectiousness Of Wild P. Falciparum Gametocytes To Anopheles Gambiae Sensu Stricto Mosquitoes

No Thumbnail Available

Date

2026-02

Journal Title

Journal ISSN

Volume Title

Publisher

NM-AIST

Abstract

Asymptomatic gametocytemic carriers serve potential harbour for Plasmodium falciparum gametocyte stage V, and a threat for malaria transmission from infected humans to Anopheles mosquitoes. Therefore, it is important to optimise direct membrane feeding assays (DMFAs) to evaluate transmission blocking interventions (TBIs) on the infectiousness of wild P. falciparum gametocytes to Anopheles mosquitoes. This study assessed the impact of artemether-lumefantrine (AL) treatment, mosquito feeding time (day vs. night), and serum replacement on the infectiousness of wild P. falciparum gametocytes to Anopheles gambiae sensu stricto (s.s) mosquitoes. To conduct this experiment, 6 gametocytemic carriers were found to be eligible and donated 4 mL of venous blood. This blood was offered to female Anopheles gambiae s.s mosquitoes via DMFA under controlled conditions. Oocyst prevalence and intensity were determined on fed mosquitoes: 1) 9 days post AL treatment, 2) day versus night feeds, and 3) with and without serum replacement. Mosquito infection rates declined post-AL treatment, with significantly fewer mosquitoes infected (odds ratio (OR) = 0.20, 95% confidence interval (CI) = 0.13-0.31, p=0.001) compared to day 0. Feeding during the mosquito night-time did not significantly affect mosquito infection rates (OR=0.77, 95% CI: 0.53-1.12, p=0.175). Lastly, serum replacement increased infection rates (OR = 1.73, 95% CI: 1.33-2.25, p = 0.001) compared to whole blood. In conclusion, we confirm that DMFA should be conducted using blood from gametocytemic participants without a recent history of AL treatment, using serum replacement to enhance infection success. In this setting, assays could be conducted during the daytime without affecting results.

Sustainable Development Goals

SDG-3: Good Health and Well-being SDG-9: Industry, Innovation and Infrastructure SDG-17: Partnerships for the Goals

Keywords

DMFA, AL, TBIs, Anopheles gambiae ss, gametocytes, oocysts, asymptomatic

Citation