1921
Volume 68, Issue 6
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645

Abstract

The seasonal dynamics and spatial distributions of mosquitoes and parasites were studied for one year at 30 villages in Malindi, Kilifi, and Kwale Districts along the coast of Kenya. Anopheline mosquitoes were sampled inside houses at each site once every two months and malaria parasite prevalence in local school children was determined at the end of the entomologic survey. A total of 5,476 and 3,461 were collected. Species in the complex, identified by a polymerase chain reaction, included 81.9% , 12.8% , and 5.3% contributed most to the transmission of along the coast as a whole, while accounted for more than 50% of all transmission in Kwale District. Large spatial heterogeneity of transmission intensity (< 1 up to 120 infective bites per person per year) resulted in correspondingly large and significantly related variations in parasite prevalence (range = 38–83%). Thirty-two percent of the sites (7 of 22 sites) with malaria prevalences ranging from 38% to 70% had annual entomologic inoculation rates (EIR) less than five infective bites per person per year. and densities in Kwale were not significantly influenced by rainfall. However, both were positively correlated with rainfall one and three months previously in Malindi and Kilifi Districts, respectively. These unexpected variations in the relationship between mosquito populations and rainfall suggest environmental heterogeneity in the predominant aquatic habitats in each district. One important conclusion is that the highly non-linear relationship between EIRs and prevalence indicates that the consistent pattern of high prevalence might be governed by substantial variation in transmission intensity measured by entomologic surveys. The field-based estimate of entomologic parameters on a district level does not provide a sensitive indicator of transmission intensity in this study.

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2003-06-01
2017-11-20
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References

  1. Hay SI, Rogers DJ, Toomer JF, Snow RW, 2000. Annual Plasmodium falciparum entomological inoculation rates (EIR) across Africa: literature survey, internet access and review. Trans R Soc Trop Med Hyg 94 : 113–127.
  2. Trape JF, Lefebvre-Zante E, Legros F, Druilhe P, Rogier C, Bouganali H, Salem G, 1993. Malaria morbidity among children exposed to low seasonal transmission in Dakar, Senegal, and its implications for malaria control in tropical Africa. Am J Trop Med Hyg 48 : 748–756.
  3. Trape JF, Rogier C, 1996. Combating malaria morbidity and mortality by reducing transmission. Parasitol Today 12 : 236–240.
  4. Mouchet J, Manguin S, Sircoulon J, Laventure S, Faye O, Onapa AW, Carnevale P, Julvez J, Fontenille D, 1998. Evolution of malaria in Africa for the past 40 years: impact of climatic and human factors. J Am Mosq Control Assoc 14 : 121–130.
  5. Beier JC, Killeen GF, Githure JI, 1999. Short report: entomologic inoculation rates and Plasmodium falciparum malaria prevalence in Africa. Am J Trop Med Hyg 61 : 109–113.
  6. Beier JC, Perkins PV, Onyango FK, Gargan TP, Oster CN, Whitmire RE, Koech DK, Roberts CR, 1990. Characterization of malaria transmission by Anopheles (Diptera: Culicidae) in western Kenya in preparation for malaria vaccine trials. J Med Entomol 27 : 570–577.
  7. Bogh C, Pedersen EM, Mukoko DA, Ouma JH, 1998. Permethrin-impregnated bednet effects on resting and feeding behaviour of lymphatic filariasis vector mosquitoes in Kenya. Med Vet Entomol 12 : 52–59.
  8. Mbogo CNM, Kabiru EW, Muiruri SK, Nzovu JM, Ouma JH, Githure JI, Beier JC, 1993. Blood-feeding behavior of Anopheles gambiae s.l. and Anopheles funestus in Kilifi District, Kenya. J Am Mosq Control Assoc 9 : 225–227.
  9. Mbogo CNM, Snow RW, Khamala CP, Kabiru EW, Ouma JH, Githure JI, Marsh K, Beier JC, 1995. Relationships between Plasmodium falciparum transmission by vector populations and the incidence of severe disease at nine sites on the Kenyan coast. Am J Trop Med Hyg 52 : 201–206.
  10. Mbogo CNM, Baya NM, Githure JI, Snow RW, 1996. The impact of permethrin-impregnated bednets on malaria vectors of the Kenyan Coast. Med Vet Entomol 10 : 251–259.
  11. Mosha FW, Mutero CM, 1982. The influence of salinity on larval development and population dynamics of Anopheles merus Dönitz (Diptera: Culicidae). Bull Entomol Res 72 : 119–128.
  12. Mosha FW, Petrarca V, 1983. Ecological studies on Anopheles gambiae complex sibling species on the Kenya coast. Trans R Soc Trop Med Hyg 77 : 344–345.
  13. Mbogo CNM, Snow RW, Kabiru EW, Ouma JH, Githure JI, Marsh K, Beier JC, 1993. Low-level Plasmodium falciparum transmission and the incidence of severe malaria infections on the Kenyan coast. Am J Trop Med Hyg 49 : 245–253.
  14. World Health Organization, 1975. Manual on Practical Entomology in Malaria. Geneva: World Health Organization. WHO offset publication No. 13.
  15. Gillies MT, 1968. The Anophelinae of Africa, South of the Sahara No. 54. (Ethiopian Zoogeographical Region). Johannesburg, South Africa: The South African Institute for Medical Research
  16. Paskewitz SM, Collins FH, 1990. Use of the polymerase chain reaction to identify mosquito species of the Anopheles gambiae complex. Med Vet Entomol 4 : 367–373.
  17. Scott JA, Brogdon WG, Collins FH, 1993. Identification of single specimens of the Anopheles gambiae complex by the polymerase chain reaction. Am J Trop Med Hyg 49 : 520–529.
  18. Wirtz RA, Burkot TR, 1991. Detection of malarial parasites in mosquitoes. Adv Dis Vect Res 8 : 77–106.
  19. Beier JC, Koros JK, 1991. Visual assessment of sporozoite and bloodmeal ELISA samples in malaria field studies. J Med Entomol 28 : 805–808.
  20. Githeko AK, Brandling-Bennett AD, Beier M, Atieli F, Owaga M, Collins FH, 1992. The reservior of Plasmodium falciparum malaria in a holoendemic area of western Kenya. Trans R Soc Trop Med Hyg 86 : 355–358.
  21. Killeen GF, Mckenzie FE, Foy BD, Schieffelin C, Billingsley PF, Beier JC, 2000. A simplified model for predicting malaria entomologic inoculation rates based on entomologic and parasitologic parameters relevant to control. Am J Trop Med Hyg 62 : 535–544.
  22. Killeen GF, Mckenzie FE, Foy BD, Schieffelin C, Billingsley PF, Beier JC, 2000. The potential impact of integrated malaria transmission control on entomologic inoculation rates in highly endemic areas. Am J Trop Med Hyg 62 : 545–551.
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  • Received : 09 Apr 2002
  • Accepted : 05 Mar 2003

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