Empowering communities for malaria control: Effectiveness of community-led biolarviciding using Bacillus thuringiensis israelensis in The Gambia

Vet World Vol.18 August-2025 Article - 1

Research Article

Veterinary World, 18(8): 2158-2168

https://doi.org/10.14202/vetworld.2025.2158-2168

Babucarr Jassey¹, Ririh Yudhastuti¹, Buba Manjang², Ibrahim Touray², Muhammad Rasyid Ridha³, Khuliyah Candraning Diyanah¹, and Fitiara Indah Permatasari⁴

1. Department of Public Health, Faculty of Public Health, Universitas Airlangga, Surabaya, Indonesia.

2. Department of Public Health Services, Ministry of Health, The Gambia, West Africa.

3. Department of Public Health, Faculty of Medicine and Health Sciences, Universitas Lambung Mangkurat, Banjarbaru, Indonesia.

4. Department of Nutrition, Faculty of Public Health, Universitas Airlangga, Surabaya, Indonesia.

Background and Aim: In The Gambia, malaria transmission persists due to insecticide resistance and residual vector behavior, despite extensive use of indoor residual spraying and insecticide-treated nets. Community-led larval source management using Bacillus thuringiensis var. israelensis (Bti) offers a sustainable vector control alternative. This study aimed to assess the effectiveness and feasibility of community-led Bti application for reducing Anopheles mosquito populations, compared to expert-supervised application and non-intervention control arms.

Materials and Methods: A non-randomized controlled trial was conducted across malaria-endemic regions in The Gambia from 2023 to 2024. Intervention arms included: (1) community-led Bti application, (2) expert-supervised Bti application, and (3) untreated control. Trained volunteers and entomologists applied Bti to breeding sites at weekly or biweekly intervals. Entomological surveys were conducted biweekly to monitor larval, pupal, and adult mosquito densities. Data were analyzed using generalized linear mixed models and negative binomial regression, adjusting for environmental covariates.

Results: By round 10, community-led and expert-supervised interventions achieved 96.8% and 98.6% reductions in larval density, 97.4% and 99.1% reductions in pupal emergence, and 96.2% and 98.8% reductions in adult mosquito populations, respectively. Statistically significant declines in mosquito densities were observed by 2024 (p < 0.001). Community participation enabled high coverage and operational sustainability, with over 85% of participants reporting visible mosquito reduction.

Conclusion: Seasonal Bti application, especially when led by trained community members, significantly suppresses Anopheles populations. Although expert-supervised methods yielded slightly higher efficacy, community-led biolarviciding offers a scalable, sustainable, and environmentally safe vector control strategy, supporting The Gambia’s malaria elimination goals.

Keywords: Anopheles mosquitoes, Bacillus thuringiensis israelensis, biolarviciding, community participation, larval source management, malaria control, The Gambia.

How to cite this article: Jassey B, Yudhastuti R, Manjang B, Touray I, Ridha MR, Diyanah KC, and Permatasari FI (2025) Empowering communities for malaria control: Effectiveness of community-led biolarviciding using Bacillus thuringiensis israelensis in The Gambia, Veterinary World, 18(8): 2158–2168.

Received: 24-03-2025 Accepted: 16-06-2025 Published online: 02-08-2025

Corresponding author: Babucarr Jassey and Ririh Yudhastuti E-mail: babucarr.jassey-2023@fkm.unair.ac.id and ririhyudhastuti@fkm.unair.ac.id

DOI: 10.14202/vetworld.2025.2158-2168

Copyright: Jassey, et al. This article is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http:// creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.