Skip to main content
Top
Published in: Malaria Journal 1/2006

Open Access 01-12-2006 | Research

Malaria hotspot areas in a highland Kenya site are consistent in epidemic and non-epidemic years and are associated with ecological factors

Authors: Kacey C Ernst, Samson O Adoka, Dickens O Kowuor, Mark L Wilson, Chandy C John

Published in: Malaria Journal | Issue 1/2006

Login to get access

Abstract

Background

Malaria epidemics in highland areas of East Africa have caused considerable morbidity and mortality in the past two decades. Knowledge of "hotspot" areas of high malaria incidence would allow for focused preventive interventions in resource-poor areas, particularly if the hotspot areas can be discerned during non-epidemic periods and predicted by ecological factors.

Methods

To address this issue, spatial distribution of malaria incidence and the relationship of ecological factors to malaria incidence were assessed in the highland area of Kipsamoite, Kenya, from 2001–2004.

Results

Clustering of disease in a single geographic "hotspot" area occurred in epidemic and non-epidemic years, with a 2.6 to 3.2-fold increased risk of malaria inside the hotspot, as compared to outside the area (P < 0.001, all 4 years). Altitude and proximity to the forest were independently associated with increased malaria risk in all years, including epidemic and non-epidemic years.

Conclusion

In this highland area, areas of high malaria risk are consistent in epidemic and non-epidemic years and are associated with specific ecological risk factors. Ongoing interventions in areas of ecological risk factors could be a cost-effective method of significantly reducing malaria incidence and blunting or preventing epidemics, even in the absence of malaria early warning systems. Further studies should be conducted to see if these findings hold true in varied highland settings.
Appendix
Available only for authorised users
Literature
1.
go back to reference Cox J CMLSDSB: Mapping malaria risk in the highlands of Africa. 1999, London, UK , MARA/HIMAL Cox J CMLSDSB: Mapping malaria risk in the highlands of Africa. 1999, London, UK , MARA/HIMAL
2.
go back to reference Staff.: Kenya's malaria death toll hits 200. SABC News. 2002, Johannesburg Staff.: Kenya's malaria death toll hits 200. SABC News. 2002, Johannesburg
3.
go back to reference Brooker S, Clarke S, Njagi JK, Polack S, Mugo B, Estambale B, Muchiri E, Magnussen P, Cox J: Spatial clustering of malaria and associated risk factors during an epidemic in a highland area of western Kenya. Trop Med Int Health. 2004, 9 (7): 757-766. 10.1111/j.1365-3156.2004.01272.x.CrossRefPubMed Brooker S, Clarke S, Njagi JK, Polack S, Mugo B, Estambale B, Muchiri E, Magnussen P, Cox J: Spatial clustering of malaria and associated risk factors during an epidemic in a highland area of western Kenya. Trop Med Int Health. 2004, 9 (7): 757-766. 10.1111/j.1365-3156.2004.01272.x.CrossRefPubMed
4.
go back to reference Lindblade KA, Walker ED, Onapa AW, Katungu J, Wilson ML: Land use change alters malaria transmission parameters by modifying temperature in a highland area of Uganda. Trop Med Int Health. 2000, 5 (4): 263-274. 10.1046/j.1365-3156.2000.00551.x.CrossRefPubMed Lindblade KA, Walker ED, Onapa AW, Katungu J, Wilson ML: Land use change alters malaria transmission parameters by modifying temperature in a highland area of Uganda. Trop Med Int Health. 2000, 5 (4): 263-274. 10.1046/j.1365-3156.2000.00551.x.CrossRefPubMed
5.
go back to reference Zhou G, Minakawa N, Githeko A, Yan G: Spatial distribution patterns of malaria vectors and sample size determination in spatially heterogeneous environments: a case study in the west Kenyan highland. J Med Entomol. 2004, 41 (6): 1001-1009.CrossRefPubMed Zhou G, Minakawa N, Githeko A, Yan G: Spatial distribution patterns of malaria vectors and sample size determination in spatially heterogeneous environments: a case study in the west Kenyan highland. J Med Entomol. 2004, 41 (6): 1001-1009.CrossRefPubMed
6.
go back to reference Kleinschmidt I, Sharp BL, Clarke GP, Curtis B, Fraser C: Use of generalized linear mixed models in the spatial analysis of small-area malaria incidence rates in Kwazulu Natal, South Africa. Am J Epidemiol. 2001, 153 (12): 1213-1221. 10.1093/aje/153.12.1213.CrossRefPubMed Kleinschmidt I, Sharp BL, Clarke GP, Curtis B, Fraser C: Use of generalized linear mixed models in the spatial analysis of small-area malaria incidence rates in Kwazulu Natal, South Africa. Am J Epidemiol. 2001, 153 (12): 1213-1221. 10.1093/aje/153.12.1213.CrossRefPubMed
7.
go back to reference MacDonald P: Natural and anthropogenic environmental factors associated with the spatial heterogeneity of adult Anopheles gambiae and An. funestus in western Kenya. Epidemiology. 2001, Ann Arbor , University of Michigan, 1: 168- MacDonald P: Natural and anthropogenic environmental factors associated with the spatial heterogeneity of adult Anopheles gambiae and An. funestus in western Kenya. Epidemiology. 2001, Ann Arbor , University of Michigan, 1: 168-
8.
go back to reference Carter R, Mendis KN, Roberts D: Spatial targeting of interventions against malaria. Bull World Health Organ. 2000, 78 (12): 1401-1411.PubMedCentralPubMed Carter R, Mendis KN, Roberts D: Spatial targeting of interventions against malaria. Bull World Health Organ. 2000, 78 (12): 1401-1411.PubMedCentralPubMed
9.
go back to reference Chadee DD, Kitron U: Spatial and temporal patterns of imported malaria cases and local transmission in Trinidad. Am J Trop Med Hyg. 1999, 61 (4): 513-517.PubMed Chadee DD, Kitron U: Spatial and temporal patterns of imported malaria cases and local transmission in Trinidad. Am J Trop Med Hyg. 1999, 61 (4): 513-517.PubMed
10.
go back to reference Kuldorff M: A spatial scan statistic. Comm Stat, Theor and Meth. 1997, 26: 1481-1496.CrossRef Kuldorff M: A spatial scan statistic. Comm Stat, Theor and Meth. 1997, 26: 1481-1496.CrossRef
11.
go back to reference John CC, McHugh MM, Moormann AM, Sumba PO, Ofulla AV: Low prevalence of Plasmodium falciparum infection among asymptomatic individuals in a highland area of Kenya. Trans R Soc Trop Med Hyg. 2005, 99 (10): 780-786.CrossRefPubMed John CC, McHugh MM, Moormann AM, Sumba PO, Ofulla AV: Low prevalence of Plasmodium falciparum infection among asymptomatic individuals in a highland area of Kenya. Trans R Soc Trop Med Hyg. 2005, 99 (10): 780-786.CrossRefPubMed
12.
go back to reference Abeku TA, de Vlas SJ, Borsboom G, Teklehaimanot A, Kebede A, Olana D, van Oortmarssen GJ, Habbema JD: Forecasting malaria incidence from historical morbidity patterns in epidemic-prone areas of Ethiopia: a simple seasonal adjustment method performs best. Trop Med Int Health. 2002, 7 (10): 851-857. 10.1046/j.1365-3156.2002.00924.x.CrossRefPubMed Abeku TA, de Vlas SJ, Borsboom G, Teklehaimanot A, Kebede A, Olana D, van Oortmarssen GJ, Habbema JD: Forecasting malaria incidence from historical morbidity patterns in epidemic-prone areas of Ethiopia: a simple seasonal adjustment method performs best. Trop Med Int Health. 2002, 7 (10): 851-857. 10.1046/j.1365-3156.2002.00924.x.CrossRefPubMed
13.
go back to reference Abeku TA, De Vlas SJ, Borsboom GJ, Tadege A, Gebreyesus Y, Gebreyohannes H, Alamirew D, Seifu A, Nagelkerke NJ, Habbema JD: Effects of meteorological factors on epidemic malaria in Ethiopia: a statistical modelling approach based on theoretical reasoning. Parasitology. 2004, 128 (Pt 6): 585-593. 10.1017/S0031182004005013.CrossRefPubMed Abeku TA, De Vlas SJ, Borsboom GJ, Tadege A, Gebreyesus Y, Gebreyohannes H, Alamirew D, Seifu A, Nagelkerke NJ, Habbema JD: Effects of meteorological factors on epidemic malaria in Ethiopia: a statistical modelling approach based on theoretical reasoning. Parasitology. 2004, 128 (Pt 6): 585-593. 10.1017/S0031182004005013.CrossRefPubMed
14.
go back to reference Hay SI, Simba M, Busolo M, Noor AM, Guyatt HL, Ochola SA, Snow RW: Defining and detecting malaria epidemics in the highlands of western Kenya. Emerg Infect Dis. 2002, 8 (6): 555-562.PubMedCentralCrossRefPubMed Hay SI, Simba M, Busolo M, Noor AM, Guyatt HL, Ochola SA, Snow RW: Defining and detecting malaria epidemics in the highlands of western Kenya. Emerg Infect Dis. 2002, 8 (6): 555-562.PubMedCentralCrossRefPubMed
15.
go back to reference Shanks GD, Hay SI, Stern DI, Biomndo K, Snow RW: Meteorologic influences on Plasmodium falciparum malaria in the Highland Tea Estates of Kericho, Western Kenya. Emerg Infect Dis. 2002, 8 (12): 1404-1408.PubMedCentralCrossRefPubMed Shanks GD, Hay SI, Stern DI, Biomndo K, Snow RW: Meteorologic influences on Plasmodium falciparum malaria in the Highland Tea Estates of Kericho, Western Kenya. Emerg Infect Dis. 2002, 8 (12): 1404-1408.PubMedCentralCrossRefPubMed
16.
go back to reference Abeku TA, van Oortmarssen GJ, Borsboom G, de Vlas SJ, Habbema JD: Spatial and temporal variations of malaria epidemic risk in Ethiopia: factors involved and implications. Acta Trop. 2003, 87 (3): 331-340. 10.1016/S0001-706X(03)00123-2.CrossRefPubMed Abeku TA, van Oortmarssen GJ, Borsboom G, de Vlas SJ, Habbema JD: Spatial and temporal variations of malaria epidemic risk in Ethiopia: factors involved and implications. Acta Trop. 2003, 87 (3): 331-340. 10.1016/S0001-706X(03)00123-2.CrossRefPubMed
17.
go back to reference Drakeley CJ, Carneiro I, Reyburn H, Malima R, Lusingu JP, Cox J, Theander TG, Nkya WM, Lemnge MM, Riley EM: Altitude-dependent and -independent variations in Plasmodium falciparum prevalence in northeastern Tanzania. J Infect Dis. 2005, 191 (10): 1589-1598. 10.1086/429669.CrossRefPubMed Drakeley CJ, Carneiro I, Reyburn H, Malima R, Lusingu JP, Cox J, Theander TG, Nkya WM, Lemnge MM, Riley EM: Altitude-dependent and -independent variations in Plasmodium falciparum prevalence in northeastern Tanzania. J Infect Dis. 2005, 191 (10): 1589-1598. 10.1086/429669.CrossRefPubMed
18.
go back to reference Bayoh MN, Lindsay SW: Effect of temperature on the development of the aquatic stages of Anopheles gambiae sensu stricto (Diptera: Culicidae). Bull Entomol Res. 2003, 93 (5): 375-381. 10.1079/BER2003259.CrossRefPubMed Bayoh MN, Lindsay SW: Effect of temperature on the development of the aquatic stages of Anopheles gambiae sensu stricto (Diptera: Culicidae). Bull Entomol Res. 2003, 93 (5): 375-381. 10.1079/BER2003259.CrossRefPubMed
19.
go back to reference Bodker R, Akida J, Shayo D, Kisinza W, Msangeni HA, Pedersen EM, Lindsay SW: Relationship between altitude and intensity of malaria transmission in the Usambara Mountains, Tanzania. J Med Entomol. 2003, 40 (5): 706-717.CrossRefPubMed Bodker R, Akida J, Shayo D, Kisinza W, Msangeni HA, Pedersen EM, Lindsay SW: Relationship between altitude and intensity of malaria transmission in the Usambara Mountains, Tanzania. J Med Entomol. 2003, 40 (5): 706-717.CrossRefPubMed
20.
go back to reference Maharaj R: Life table characteristics of Anopheles arabiensis (Diptera: Culicidae) under simulated seasonal conditions. J Med Entomol. 2003, 40 (6): 737-742.CrossRefPubMed Maharaj R: Life table characteristics of Anopheles arabiensis (Diptera: Culicidae) under simulated seasonal conditions. J Med Entomol. 2003, 40 (6): 737-742.CrossRefPubMed
21.
go back to reference Ndenga B, Githeko A, Omukunda E, Munyekenye G, Atieli H, Wamai P, Mbogo C, Minakawa N, Zhou G, Yan G: Population dynamics of malaria vectors in western Kenya highlands. J Med Entomol. 2006, 43 (2): 200-206.CrossRefPubMed Ndenga B, Githeko A, Omukunda E, Munyekenye G, Atieli H, Wamai P, Mbogo C, Minakawa N, Zhou G, Yan G: Population dynamics of malaria vectors in western Kenya highlands. J Med Entomol. 2006, 43 (2): 200-206.CrossRefPubMed
22.
go back to reference Minakawa N, Sonye G, Mogi M, Yan G: Habitat characteristics of Anopheles gambiae s.s. larvae in a Kenyan highland. Med Vet Entomol. 2004, 18 (3): 301-305. 10.1111/j.0269-283X.2004.00503.x.CrossRefPubMed Minakawa N, Sonye G, Mogi M, Yan G: Habitat characteristics of Anopheles gambiae s.s. larvae in a Kenyan highland. Med Vet Entomol. 2004, 18 (3): 301-305. 10.1111/j.0269-283X.2004.00503.x.CrossRefPubMed
23.
go back to reference Tuno N, Okeka W, Minakawa N, Takagi M, Yan G: Survivorship of Anopheles gambiae sensu stricto (Diptera: Culicidae) larvae in western Kenya highland forest. J Med Entomol. 2005, 42 (3): 270-277.CrossRefPubMed Tuno N, Okeka W, Minakawa N, Takagi M, Yan G: Survivorship of Anopheles gambiae sensu stricto (Diptera: Culicidae) larvae in western Kenya highland forest. J Med Entomol. 2005, 42 (3): 270-277.CrossRefPubMed
24.
go back to reference Mbogo CN, Kabiru EW, Glass GE, Forster D, Snow RW, Khamala CP, Ouma JH, Githure JI, Marsh K, Beier JC: Vector-related case-control study of severe malaria in Kilifi District, Kenya. Am J Trop Med Hyg. 1999, 60 (5): 781-785.PubMed Mbogo CN, Kabiru EW, Glass GE, Forster D, Snow RW, Khamala CP, Ouma JH, Githure JI, Marsh K, Beier JC: Vector-related case-control study of severe malaria in Kilifi District, Kenya. Am J Trop Med Hyg. 1999, 60 (5): 781-785.PubMed
25.
go back to reference Gamage-Mendis AC, Carter R, Mendis C, De Zoysa AP, Herath PR, Mendis KN: Clustering of malaria infections within an endemic population: risk of malaria associated with the type of housing construction. Am J Trop Med Hyg. 1991, 45 (1): 77-85.PubMed Gamage-Mendis AC, Carter R, Mendis C, De Zoysa AP, Herath PR, Mendis KN: Clustering of malaria infections within an endemic population: risk of malaria associated with the type of housing construction. Am J Trop Med Hyg. 1991, 45 (1): 77-85.PubMed
26.
go back to reference Bashford G, Richens J: Travel to the coast by highlanders and its implications for malaria control. P N G Med J. 1992, 35 (4): 306-307.PubMed Bashford G, Richens J: Travel to the coast by highlanders and its implications for malaria control. P N G Med J. 1992, 35 (4): 306-307.PubMed
27.
go back to reference Hay SI, Noor AM, Simba M, Busolo M, Guyatt HL, Ochola SA, Snow RW: Clinical epidemiology of malaria in the highlands of western Kenya. Emerg Infect Dis. 2002, 8 (6): 543-548.PubMedCentralCrossRefPubMed Hay SI, Noor AM, Simba M, Busolo M, Guyatt HL, Ochola SA, Snow RW: Clinical epidemiology of malaria in the highlands of western Kenya. Emerg Infect Dis. 2002, 8 (6): 543-548.PubMedCentralCrossRefPubMed
28.
go back to reference Lindblade KA, Walker ED, Wilson ML: Early warning of malaria epidemics in African highlands using Anopheles (Diptera: Culicidae) indoor resting density. J Med Entomol. 2000, 37 (5): 664-674.CrossRefPubMed Lindblade KA, Walker ED, Wilson ML: Early warning of malaria epidemics in African highlands using Anopheles (Diptera: Culicidae) indoor resting density. J Med Entomol. 2000, 37 (5): 664-674.CrossRefPubMed
Metadata
Title
Malaria hotspot areas in a highland Kenya site are consistent in epidemic and non-epidemic years and are associated with ecological factors
Authors
Kacey C Ernst
Samson O Adoka
Dickens O Kowuor
Mark L Wilson
Chandy C John
Publication date
01-12-2006
Publisher
BioMed Central
Published in
Malaria Journal / Issue 1/2006
Electronic ISSN: 1475-2875
DOI
https://doi.org/10.1186/1475-2875-5-78

Other articles of this Issue 1/2006

Malaria Journal 1/2006 Go to the issue
Live Webinar | 27-06-2024 | 18:00 (CEST)

Keynote webinar | Spotlight on medication adherence

Live: Thursday 27th June 2024, 18:00-19:30 (CEST)

WHO estimates that half of all patients worldwide are non-adherent to their prescribed medication. The consequences of poor adherence can be catastrophic, on both the individual and population level.

Join our expert panel to discover why you need to understand the drivers of non-adherence in your patients, and how you can optimize medication adherence in your clinics to drastically improve patient outcomes.

Prof. Kevin Dolgin
Prof. Florian Limbourg
Prof. Anoop Chauhan
Developed by: Springer Medicine
Obesity Clinical Trial Summary

At a glance: The STEP trials

A round-up of the STEP phase 3 clinical trials evaluating semaglutide for weight loss in people with overweight or obesity.

Developed by: Springer Medicine

Highlights from the ACC 2024 Congress

Year in Review: Pediatric cardiology

Watch Dr. Anne Marie Valente present the last year's highlights in pediatric and congenital heart disease in the official ACC.24 Year in Review session.

Year in Review: Pulmonary vascular disease

The last year's highlights in pulmonary vascular disease are presented by Dr. Jane Leopold in this official video from ACC.24.

Year in Review: Valvular heart disease

Watch Prof. William Zoghbi present the last year's highlights in valvular heart disease from the official ACC.24 Year in Review session.

Year in Review: Heart failure and cardiomyopathies

Watch this official video from ACC.24. Dr. Biykem Bozkurt discusses last year's major advances in heart failure and cardiomyopathies.