Anopheles larval ecology and physicochemical characterization of larval habitats in Dire Dawa: an area colonized by Anopheles stephensi in Eastern Ethiopia.
8 affiliations
- 1School of Medical Laboratory Sciences, Institute of Health, Jimma University, Jimma, Ethiopia. [email protected].
- 2Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia. [email protected].
- 3School of Medical Laboratory Sciences, Institute of Health, Jimma University, Jimma, Ethiopia.
- 4Aklilu Lemma Institute of Health Research (ALIHR), Addis Ababa University, Addis Ababa, Ethiopia.
- 5Department of Epidemiology, Institute of Health, Jimma University, Jimma, Ethiopia.
- 6Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia.
- 7Tom Mboya University, Homa Bay, Kenya.
- 8Department of Population Health and Disease Prevention, Joe C. Wen School of Population and Public Health, University of California at Irvine, Irvine, USA.
Abstract
Background
Understanding mosquito larval ecology is crucial for effective vector control strategies. While much is known about Anopheles larval habitat distribution, the impact of landscape (urban vs. rural) on Anopheles stephensi larval distribution and population dynamics in Ethiopia remains unclear.Methods
A longitudinal study was conducted from February 2023 to December 2024 in aquatic habitats in urban, peri-urban, and rural areas of Dire Dawa City Administration, eastern Ethiopia. Mosquito larvae and pupae were collected and reared in a field insectary until adult emergence. The female Anopheles were morphologically identified and further confirmed via polymerase chain reaction (PCR). The physicochemical parameters of the larval habitats were measured via a HANNA multiparameter water probe. Statistical analyses included general linear models, ANOVA, logistic regression, paired sample t tests, chi-square tests, principal component analysis and correlation analyses to assess larval presence, density, and distribution in relation to water physicochemical parameters across the three ecological settings.Results
A total of 23,526 larvae and 1808 pupae of Anopheles mosquitoes were collected from 856 man-made habitats (bricks, plastic sheets, steel drums, tire tracks, canal ditches, and barrels) and 53 natural habitats (river edges, animal hoof prints, ponds, and swamps) in urban, peri-urban, and rural areas. Uncovered cemented cisterns were the main human-made larval habitats; river edges were the main natural habitats. Anopheles larvae were absent in the steel drums and plastic barrels at the rural sites. Anopheles larval density significantly differed across the different ecological settings (F = 7.8, df = 1, 908, p = 0.005) and among the different larval habitat types (F = 326.2, df = 1, 907, p < 0.001). Among the 2934 reared adults, 74.8% (2194/2934) were An. stephensi, 21.7% (636/2934) were An. arabiensis, and 3.0% were other species (An. pharoensis, An. coustani, An. amharicus, An. pretoriensis). An. stephensi shares habitats with An. arabiensis and An. amharicus. Larval presence was significantly associated with brick factory proximity (χ2 = 23.8, df = 5, p < 0.001), land use/surrounding environment (χ2 = 32.6, df = 13, p = 0.002), vegetation (χ2 = 27.1, df = 12, p = 0.008), shade coverage (χ2 = 25.9, df = 15, p = 0.039), substrate type (χ2 = 34.1, df = 6, p < 0.001), and competitor/predator presence (χ2 = 14.6, df = 1, p = 0.001). However, larval presence was not associated with the presence of larval interventions (χ2 = 1.3, df = 1, p = 0.250). Water pH (r = 0.26, n = 102, p < 0.050) and water pressure (r = 0.21, n = 102, p < 0.050) were the only water physicochemical parameters that were positively correlated with An. stephensi presence.Conclusion
Anopheles stephensi was dominant in urban areas but was also present in rural areas. Existing larval source management methods do not prevent Anopheles from occurring in many habitats, indicating an urgent need for improved strategies.
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BibTeX
@article{abiy2026anopheles,
title = {{Anopheles larval ecology and physicochemical characterization of larval habitats in Dire Dawa: an area colonized by Anopheles stephensi in Eastern Ethiopia.}},
author = {Ephrem Abiy and Teshome Degefa and Meshesha Balkew and Hailu Merga and Deneke Zewdu and Alamayo Ayala and Harrysone Atieli and Ming-Chieh Lee and Guofa Zhou and Guiyun Yan and Delenasaw Yewhalaw},
journal = {Malaria journal},
year = {2026},
month = aug,
doi = {10.1186/s12936-026-06082-w},
url = {https://europepmc.org/article/MED/42958273},
note = {CC BY},
}
RIS
TY - JOUR
TI - Anopheles larval ecology and physicochemical characterization of larval habitats in Dire Dawa: an area colonized by Anopheles stephensi in Eastern Ethiopia.
AU - Ephrem Abiy
AU - Teshome Degefa
AU - Meshesha Balkew
AU - Hailu Merga
AU - Deneke Zewdu
AU - Alamayo Ayala
AU - Harrysone Atieli
AU - Ming-Chieh Lee
AU - Guofa Zhou
AU - Guiyun Yan
AU - Delenasaw Yewhalaw
PY - 2026
DA - 2026/08/01
JO - Malaria journal
DO - 10.1186/s12936-026-06082-w
UR - https://europepmc.org/article/MED/42958273
AB - Background Understanding mosquito larval ecology is crucial for effective vector control strategies. While much is known about Anopheles larval habitat distribution, the impact of landscape (urban vs. rural) on Anopheles stephensi larval distribution and population dynamics in Ethiopia remains unclear.Methods A longitudinal study was conducted from February 2023 to December 2024 in aquatic habitats in urban, peri-urban, and rural areas of Dire Dawa City Administration, eastern Ethiopia. Mosquito larvae and pupae were collected and reared in a field insectary until adult emergence. The female Anopheles were morphologically identified and further confirmed via polymerase chain reaction (PCR). The physicochemical parameters of the larval habitats were measured via a HANNA multiparameter water probe. Statistical analyses included general linear models, ANOVA, logistic regression, paired sample t tests, chi-square tests, principal component analysis and correlation analyses to assess larval presence, density, and distribution in relation to water physicochemical parameters across the three ecological settings.Results A total of 23,526 larvae and 1808 pupae of Anopheles mosquitoes were collected from 856 man-made habitats (bricks, plastic sheets, steel drums, tire tracks, canal ditches, and barrels) and 53 natural habitats (river edges, animal hoof prints, ponds, and swamps) in urban, peri-urban, and rural areas. Uncovered cemented cisterns were the main human-made larval habitats; river edges were the main natural habitats. Anopheles larvae were absent in the steel drums and plastic barrels at the rural sites. Anopheles larval density significantly differed across the different ecological settings (F = 7.8, df = 1, 908, p = 0.005) and among the different larval habitat types (F = 326.2, df = 1, 907, p < 0.001). Among the 2934 reared adults, 74.8% (2194/2934) were An. stephensi, 21.7% (636/2934) were An. arabiensis, and 3.0% were other species (An. pharoensis, An. coustani, An. amharicus, An. pretoriensis). An. stephensi shares habitats with An. arabiensis and An. amharicus. Larval presence was significantly associated with brick factory proximity (χ2 = 23.8, df = 5, p < 0.001), land use/surrounding environment (χ2 = 32.6, df = 13, p = 0.002), vegetation (χ2 = 27.1, df = 12, p = 0.008), shade coverage (χ2 = 25.9, df = 15, p = 0.039), substrate type (χ2 = 34.1, df = 6, p < 0.001), and competitor/predator presence (χ2 = 14.6, df = 1, p = 0.001). However, larval presence was not associated with the presence of larval interventions (χ2 = 1.3, df = 1, p = 0.250). Water pH (r = 0.26, n = 102, p < 0.050) and water pressure (r = 0.21, n = 102, p < 0.050) were the only water physicochemical parameters that were positively correlated with An. stephensi presence.Conclusion Anopheles stephensi was dominant in urban areas but was also present in rural areas. Existing larval source management methods do not prevent Anopheles from occurring in many habitats, indicating an urgent need for improved strategies.
SN - 1475-2875
ER -