Geospatial modelling of dry season habitats of the malaria vector, Anopheles funestus, in south-eastern Tanzania
Abstract Background Anopheles funestus is a major malaria vector in Eastern and Southern Africa and is currently the dominant malaria-transmitting vector in many parts of Tanzania. Previous research has identified its preference for specific aquatic habitats, especially those that persist in dry mon...
| Main Authors: | , , , , , , , |
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| Format: | Article |
| Language: | English |
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BMC
2024-01-01
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| Series: | Parasites & Vectors |
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| Online Access: | https://doi.org/10.1186/s13071-024-06119-6 |
| _version_ | 1797275664822304768 |
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| author | Najat F. Kahamba Fredros O. Okumu Mohammed Jumanne Khamisi Kifungo Joel O. Odero Francesco Baldini Heather M. Ferguson Luca Nelli |
| author_facet | Najat F. Kahamba Fredros O. Okumu Mohammed Jumanne Khamisi Kifungo Joel O. Odero Francesco Baldini Heather M. Ferguson Luca Nelli |
| author_sort | Najat F. Kahamba |
| collection | DOAJ |
| description | Abstract Background Anopheles funestus is a major malaria vector in Eastern and Southern Africa and is currently the dominant malaria-transmitting vector in many parts of Tanzania. Previous research has identified its preference for specific aquatic habitats, especially those that persist in dry months. This observation suggests the potential for targeted control through precise habitat mapping and characterization. In this study, we investigated the influence of habitat characteristics, land cover and human population densities on An. funestus distribution during dry seasons. Based on the results, we developed a habitat suitability model for this vector species in south-eastern Tanzania. Methods Eighteen villages in south-eastern Tanzania were surveyed during the dry season from September-December 2021. Water bodies were systematically inspected for mosquito larvae and characterized by their physico-chemical characteristics and surrounding environmental features. A generalized linear model was used to assess the presence of An. funestus larvae as a function of the physico-chemical characteristics, land use and human population densities. The results obtained from this model were used to generate spatially explicit predictions of habitat suitability in the study districts. Results Of the 1466 aquatic habitats surveyed, 440 were positive for An. funestus, with river streams having the highest positivity (74%; n = 322) followed by ground pools (15%; n = 67). The final model had an 83% accuracy in predicting positive An. funestus habitats, with the most important characteristics being permanent waters, clear waters with or without vegetation or movement and shading over the habitats. There was also a positive association of An. funestus presence with forested areas and a negative association with built-up areas. Human population densities had no influence on An. funestus distribution. Conclusions The results of this study underscore the crucial role of both the specific habitat characteristics and key environmental factors, notably land cover, in the distribution of An. funestus. In this study area, An. funestus predominantly inhabits river streams and ground pools, with a preference for clear, perennial waters with shading. The strong positive association with more pristine environments with tree covers and the negative association with built-up areas underscore the importance of ecological transitions in vector distribution and malaria transmission risk. Such spatially explicit predictions could enable more precise interventions, particularly larval source management, to accelerate malaria control. Graphical Abstract |
| first_indexed | 2024-03-07T15:17:43Z |
| format | Article |
| id | doaj.art-17d1f1a4f6e4475f821ee02b7a7badf6 |
| institution | Directory Open Access Journal |
| issn | 1756-3305 |
| language | English |
| last_indexed | 2024-03-07T15:17:43Z |
| publishDate | 2024-01-01 |
| publisher | BMC |
| record_format | Article |
| series | Parasites & Vectors |
| spelling | doaj.art-17d1f1a4f6e4475f821ee02b7a7badf62024-03-05T17:50:42ZengBMCParasites & Vectors1756-33052024-01-0117111410.1186/s13071-024-06119-6Geospatial modelling of dry season habitats of the malaria vector, Anopheles funestus, in south-eastern TanzaniaNajat F. Kahamba0Fredros O. Okumu1Mohammed Jumanne2Khamisi Kifungo3Joel O. Odero4Francesco Baldini5Heather M. Ferguson6Luca Nelli7Environmental Health and Ecological Sciences Department, Ifakara Health InstituteEnvironmental Health and Ecological Sciences Department, Ifakara Health InstituteEnvironmental Health and Ecological Sciences Department, Ifakara Health InstituteEnvironmental Health and Ecological Sciences Department, Ifakara Health InstituteEnvironmental Health and Ecological Sciences Department, Ifakara Health InstituteSchool of Biodiversity, One Health and Veterinary Medicine, University of GlasgowEnvironmental Health and Ecological Sciences Department, Ifakara Health InstituteSchool of Biodiversity, One Health and Veterinary Medicine, University of GlasgowAbstract Background Anopheles funestus is a major malaria vector in Eastern and Southern Africa and is currently the dominant malaria-transmitting vector in many parts of Tanzania. Previous research has identified its preference for specific aquatic habitats, especially those that persist in dry months. This observation suggests the potential for targeted control through precise habitat mapping and characterization. In this study, we investigated the influence of habitat characteristics, land cover and human population densities on An. funestus distribution during dry seasons. Based on the results, we developed a habitat suitability model for this vector species in south-eastern Tanzania. Methods Eighteen villages in south-eastern Tanzania were surveyed during the dry season from September-December 2021. Water bodies were systematically inspected for mosquito larvae and characterized by their physico-chemical characteristics and surrounding environmental features. A generalized linear model was used to assess the presence of An. funestus larvae as a function of the physico-chemical characteristics, land use and human population densities. The results obtained from this model were used to generate spatially explicit predictions of habitat suitability in the study districts. Results Of the 1466 aquatic habitats surveyed, 440 were positive for An. funestus, with river streams having the highest positivity (74%; n = 322) followed by ground pools (15%; n = 67). The final model had an 83% accuracy in predicting positive An. funestus habitats, with the most important characteristics being permanent waters, clear waters with or without vegetation or movement and shading over the habitats. There was also a positive association of An. funestus presence with forested areas and a negative association with built-up areas. Human population densities had no influence on An. funestus distribution. Conclusions The results of this study underscore the crucial role of both the specific habitat characteristics and key environmental factors, notably land cover, in the distribution of An. funestus. In this study area, An. funestus predominantly inhabits river streams and ground pools, with a preference for clear, perennial waters with shading. The strong positive association with more pristine environments with tree covers and the negative association with built-up areas underscore the importance of ecological transitions in vector distribution and malaria transmission risk. Such spatially explicit predictions could enable more precise interventions, particularly larval source management, to accelerate malaria control. Graphical Abstracthttps://doi.org/10.1186/s13071-024-06119-6Habitat characterizationLarval ecologyMosquito distributionEnvironmental factorsLand cover analysisAquatic habitat mapping |
| spellingShingle | Najat F. Kahamba Fredros O. Okumu Mohammed Jumanne Khamisi Kifungo Joel O. Odero Francesco Baldini Heather M. Ferguson Luca Nelli Geospatial modelling of dry season habitats of the malaria vector, Anopheles funestus, in south-eastern Tanzania Parasites & Vectors Habitat characterization Larval ecology Mosquito distribution Environmental factors Land cover analysis Aquatic habitat mapping |
| title | Geospatial modelling of dry season habitats of the malaria vector, Anopheles funestus, in south-eastern Tanzania |
| title_full | Geospatial modelling of dry season habitats of the malaria vector, Anopheles funestus, in south-eastern Tanzania |
| title_fullStr | Geospatial modelling of dry season habitats of the malaria vector, Anopheles funestus, in south-eastern Tanzania |
| title_full_unstemmed | Geospatial modelling of dry season habitats of the malaria vector, Anopheles funestus, in south-eastern Tanzania |
| title_short | Geospatial modelling of dry season habitats of the malaria vector, Anopheles funestus, in south-eastern Tanzania |
| title_sort | geospatial modelling of dry season habitats of the malaria vector anopheles funestus in south eastern tanzania |
| topic | Habitat characterization Larval ecology Mosquito distribution Environmental factors Land cover analysis Aquatic habitat mapping |
| url | https://doi.org/10.1186/s13071-024-06119-6 |
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