International Journal of Tropical Insect Science

, Volume 23, Issue 3, pp 187–196 | Cite as

Spatial Distribution of Anopheles gambiae and Anopheles funestus and Malaria Transmission in Suba District, Western Kenya

  • Josephat I. ShililuEmail author
  • Charles M. Mbogo
  • Clifford M. Mutero
  • James T. Gunter
  • Chris Swalm
  • James L. Regens
  • Joseph Keating
  • Guiyun Yan
  • John I. Githure
  • John C. Beier
Research Article


The study reported here evaluated the distribution, relative abundance, and malaria transmission potential of Anopheles mosquitoes at 30 sites representing different ecological strata in western Kenya. Seasonal variation in anopheline densities and transmission potential, as expressed by Entomological inoculation rates (EIR), was investigated. Of the 6491 indoor resting anopheline mosquitoes collected at the 30 sites, 91.3 % (n = 5926) were An. gambiae s.l. and 8.7 % (n = 565) were An. funestus with an average house density of 6.58 and 0.63, respectively. Analysis of the data indicated significant variation in mosquito densities between study sites, species and season. High densities of both An. gambiae and An. funestus were recorded in the northern and northeastern parts of the district, while generally low densities were recorded in the south. Anopheles gambiae s.s. and An. arabiensis comprised 60.3 % (n = 3573) and 39.7 % (n = 2352) of the total number of An. gambiae s.l. mosquitoes collected, respectively. The composition of the An. gambiae s.l. sibling species showed temporal and spatial variation. Entomologic inoculation rates were estimated at 1.55 and 0.12 infective bites per person per month for An. gambiae s.l. and An. funestus, respectively. This study reveals considerable seasonal and site-specific variation in vector distribution, composition and transmission potential. Application of control interventions must therefore consider seasonal variations since the vectorial system changes quite rapidly over a short period of time.

Key Words

Anopheles gambaie Anopheles funestus spatial distribution EIR vector control 


L’étude présentée ici évalue la distribution, l’abondance relative, et le potentiel de transmission du paludisme par des moustiques anophèles dans 30 localités représentatives des différentes conditions écologiques de l’Ouest du Kenya. La variation saisonnière des densités d’anophèles et du potentiel de transmission, exprimées par les taux d’inoculations Entomologiques (EIR), est examinée. Sur les 6491 anophèles récoltées au repos à l’intérieur des maisons dans les 30 localités, 91,3% (n=5926) sont des An. gambiae s.l. et 8,7% sont des An. funeslus avec une densité moyenne par maison de 6,58 et 0,63 respectivement. L’analyse des données indique une variation significative des densités de moustiques entre les sites étudiés, l’espèce et la saison. Des densités élevées à la fois d’An, gambiae s.l. et An. funestus ont été observées dans le nord et le nord est du district, alors que des densités généralement faibles ont été observées dans le sud. An. gambiae s.S. et An. arabiensis représentent respectivement 60,3% (n=3573) et 39,7% (n=2352) du nombre total de An. gambiae s.l récolté. La composition des 2 espèces d’An, gambiae s.l. montre une variation temporelle et spatiale. Les taux d’inoculations entomologiques sont estimés respectivement à 1,55 et 0,12 piqûres infestantes par personne et par mois pour’An. gambiae s.l. et An. funestus. Cette étude révèle une variation considérable de la distribution, de la composition et du potentiel de transmission des vecteurs selon la saison et la localité. La réalisation de campagnes de lutte doit par conséquent prendre en compte les variations saisonnières puisque le complexe vectoriel change très rapidement en un temps très court.

Mots Clés

Anopheles gambaie Anopheles funestus distribution spatiale EIR contrôle vectoriel 


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  1. Attenborough R. D., Burkot T. R. and Gardner D. S. (1997) Altitude and the risk bites from mosquitoes infected with malaria and filariasis among the Mianmin people of Papua New Guinea. Trans. R. Trop. Med. Hyg. 91, 8–10.CrossRefGoogle Scholar
  2. Beier J. C., Perkins P. V., Wirtz R. A., Whitmire R. E., Mugambi M. and Hockmeyer W. T. (1987) Field evaluation of an enzyme-linked immunosorbent assay (ELISA) for Plasmodium falciparum sporozoite detection in anopheline mosquitoes from Kenya. Am. J. Trop. Med. Hyg. 36, 459–468.CrossRefGoogle Scholar
  3. Beier J. C., Perkins P. V., Onyango F. K., Gargan T. P., Oster M. C., Whitmire R. E., Koech D. K. and Clifford R. R. (1990) Characterization of malaria transmission by Anopheles (Diptera: Culicidae) in western Kenya in preparation for malaria vaccine trials, J. Med. Entomol. 27, 570–577.CrossRefGoogle Scholar
  4. Coetzee M., Craig M. and Le Sueur D. (2000) Distribution of African malaria mosquitoes belonging to the Anopheles gambiae complex. Parasitol Today 16, 74–77.CrossRefGoogle Scholar
  5. Collins F. H., Mendez M. A., Rasnussen M., Mehaffey P. C., Besansky N. J. and Finnerty V. (1987) A ribosomal RNA gene probe differentiates member species of the Anopheles gambiae complex. Am. J. Trop. Med. Hyg. 37, 37–41.CrossRefGoogle Scholar
  6. Gillies M. T. and Coetzee M. (1987) A supplement of the Anopheline of Africa South of the Sahara (Afrotropical Region). Pub. S. Afr. Inst. Med. Res, 55.Google Scholar
  7. Githeko A. K., Service M. W., Mbogo C. M., Atieli F. K. and Juma F. O. (1993) Plasmodium falciparum sporozoite and entomological inoculation rates at Ahero rice irrigation scheme and the Miwani sugarbelt in western Kenya. Ann. Trop. Med. Parasitol. 87, 379–391.CrossRefGoogle Scholar
  8. Highton R. B., Bryan J. H., Boreham P. F. L. and Chandler J. A. (1979) Studies on the sibling species Anopheles gambiae Giles and An. arabiensis Patton (Diptera: Culicidae) in the Kisumu area, Kenya. Bull. Entomol. Res. 69, 43–53.CrossRefGoogle Scholar
  9. Kenya National Bureau of Statistics(1999) Executive Report: Summary Statistics. Government Press, Nairobi, Kenya.Google Scholar
  10. Lindblade A. K., Walker E. D. and Wilson M. L. (2000) Early warning of malaria epidemics in African highlands using Anopheles (Diptera: Culicidae) indoor resting densities, J. Med. Entomol. 37, 664–674.CrossRefGoogle Scholar
  11. Lindsay S. W., Campbell H., Adiainhah J. H., Greenwood A. M., Bangali S. E. and Greenwood B. M. (1990) Malaria in a peri-urban area of the Gambia. Ann. Trop. Med. Parasitol. 84, 555–562.CrossRefGoogle Scholar
  12. Mbogo C. M., Snow R. W., Khamala C. P., Kabiru E. W., Ouma J. H., Githure J. I., Marsh K. and Beier J. C. (1995) Relationships between Plasmodium falciparum transmission by vector populations and the incidence of severe disease at nine sites on the Kenya coast. Am. J. Trop. Med. Hyg. 52, 201–206.CrossRefGoogle Scholar
  13. Minakawa N., Mutero C. M., Githure J. I., Beier J. C. and Yan G. (1999) Spatial distribution and habitat characterization of anopheline mosquito larvae in western Kenya. Am. J. Trop. Med. Hyg. 37, 37–41.Google Scholar
  14. Mutero C. M., Ouma J. H., Agak B. K., Wanderi J. A. and Copeland R. S. (1998) Malaria prevalence and use of self-protection measures against mosquitoes in Suba District, Kenya. East Afr. Med. J. 75, 11–16.PubMedGoogle Scholar
  15. Omumbo J., Ouma J. H., Rapuoda B., Craig M. H., Le Sueur D. and Snow R. W. (1998) Mapplng malaria transmission using geographical information systems (GIS): An example from Kenya. Trop. Med. Parasitol. 92, 7–21.CrossRefGoogle Scholar
  16. Petrarca V., Beier J. C., Onyango F. K., Koros J. K., Asiago C. M., Koech D. K. and Roberts C. R. (1991) Species composition of Anopheles gambiae complex (Diptera: Culicidae) at two sites in western Kenya, J. Med. Entomol. 28, 307–313.CrossRefGoogle Scholar
  17. Scott J. A., Brogdon W. G. and Collins F. K. (1993) Identification of single specimens of the Anopheles gambiae complex by polymerase chain reaction. Am. J. Trop. Med. Hyg. 49, 520–529.CrossRefGoogle Scholar
  18. Shililu J. I., Maier W. A., Seitz H. M. and Orago A. S. (1998) Seasonal density, sporozoite rates and entomological inoculation rates of Anopheles gambiae and Anopheles funestus in a high-altitude sugarcane zone in Western Kenya. Trop. Med. Int. Health. 3, 706–710.CrossRefGoogle Scholar

Copyright information

© ICIPE 2003

Authors and Affiliations

  • Josephat I. Shililu
    • 1
    Email author
  • Charles M. Mbogo
    • 2
  • Clifford M. Mutero
    • 3
    • 8
  • James T. Gunter
    • 4
  • Chris Swalm
    • 6
  • James L. Regens
    • 4
  • Joseph Keating
    • 5
  • Guiyun Yan
    • 7
  • John I. Githure
    • 1
  • John C. Beier
    • 9
  1. 1.Hurnan Health DivisionInternational Centre of Insect Physiology and Ecology (ICIPE)NairobiKenya
  2. 2.Centre for Geographic Medicine Research-CoastKenya Medical Research Institute (KEMRI)KilifiKenya
  3. 3.Jomo Kenyatta University of Agriculture and TechnologyNairobiKenya
  4. 4.Institute for Science and Public Policy, Sarkeys Energy CenterUniversity of OklahomaNormanUSA
  5. 5.Deparrment of International Health and Development, TB46, School of Public Health and Tropical MedicineTulane UniversityNew OrleansUSA
  6. 6.Department of PharmacologyTulane University Health Science Center SL18New OrleansUSA
  7. 7.Department of Biological SciencesState University of New York at BuffaloBuffaloUSA
  8. 8.CGIAR System-wide Initiative on Malaria and Agriculture (SIMA)International Water Management Institute (IMWI)Silverton, PretoriaSouth Africa
  9. 9.Department of Tropical Medicine, School of Public Health and Tropical Medicine, SL 17Tulane UniversityNew OrleansUSA

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