Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-27T06:10:53.140Z Has data issue: false hasContentIssue false
  • English
  • Français

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

Published online by Cambridge University Press:  19 September 2011

Josephat I. Shililu ,
Charles M. Mbogo ,
Clifford M. Mutero ,
James T. Gunter ,
Chris Swalm ,
James L. Regens ,
Joseph Keating ,
Guiyun Yan ,
John I. Githure  and
John C. Beier
Josephat I. Shililu
Affiliation:
Hurnan Health Division, International Centre of Insect Physiology and Ecology (ICIPE), P. O. Box 30772–00100 Nairobi, Kenya Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
Charles M. Mbogo
Affiliation:
Centre for Geographic Medicine Research-Coast, Kenya Medical Research Institute (KEMRI), P. O. Box 428, Kilifi, Kenya
Clifford M. Mutero
Affiliation:
Hurnan Health Division, International Centre of Insect Physiology and Ecology (ICIPE), P. O. Box 30772–00100 Nairobi, Kenya CGIAR System-wide Initiative on Malaria and Agriculture (SIMA), International Water Management Institute (IMWI), 141 Creswell Street, Silverton 0184, Private Bag X 813, 0127 Silverton, Pretoria, South Africa
James T. Gunter
Affiliation:
Institute for Science and Public Policy, Sarkeys Energy Center, University of Oklahoma, 100 E. Boyd Room 510, Norman, OK 73019–1006, USA
Chris Swalm
Affiliation:
Department of Pharmacology, Tulane University Health Science Center SL18, 1430 Tulane Av, New Orleans, LA 70112–2699, USA
James L. Regens
Affiliation:
Institute for Science and Public Policy, Sarkeys Energy Center, University of Oklahoma, 100 E. Boyd Room 510, Norman, OK 73019–1006, USA
Joseph Keating
Affiliation:
Deparrment of International Health and Development, TB46, School of Public Health and Tropical Medicine, Tulane University, 1440 Canal St., New Orleans, LA 70112, USA
Guiyun Yan
Affiliation:
Department of Biological Sciences, State University of New York at Buffalo, Buffalo, NY 14260, USA
John I. Githure
Affiliation:
Hurnan Health Division, International Centre of Insect Physiology and Ecology (ICIPE), P. O. Box 30772–00100 Nairobi, Kenya
John C. Beier
Affiliation:
Department of Tropical Medicine, School of Public Health and Tropical Medicine, SL 17, Tulane University 1430 Tulane Ave., New Orleans, LA 70112, USA
Get access

Abstract

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.

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.

Keywords

Anopheles gambaieAnopheles funestusspatial distributionEIRvector controlAnopheles gambaieAnopheles funestusdistribution spatialeEIRcontrôle vectoriel
Type
Research Articles
Information
International Journal of Tropical Insect Science , Volume 23 , Issue 3 , September 2003 , pp. 187 - 196
Copyright
Copyright © ICIPE 2003

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

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 ScholarPubMed
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 ScholarPubMed
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 ScholarPubMed
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
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 ScholarPubMed
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
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 ScholarPubMed
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
Kenya National Bureau of Statistics (1999) Executive Report: Summary Statistics. Government Press, Nairobi, Kenya.Google Scholar
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
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
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
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
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.Google ScholarPubMed
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 ScholarPubMed
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 ScholarPubMed
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 ScholarPubMed
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