title: Heterogeneity and changes in inequality of malaria risk after introduction of insecticide-treated bed nets in Macha, Zambia.
abstract: In 2007, the first free mass distribution of insecticide-treated bed nets (ITNs) occurred in southern Zambia. To determine the effect of ITNs on heterogeneity in biting rates, human DNA from Anopheles arabiensis blood meals was genotyped to determine the number of hosts that had contributed to the blood meals. The multiple feeding rate decreased from 18.9% pre-ITN to 9.1% post-ITN, suggesting that mosquito biting had focused onto a smaller fraction of the population. Pre-ITN, 20% of persons in a household provided 40% of blood meals, which increased to 59% post-ITN. To measure heterogeneity over a larger scale, mosquitoes were collected in 90 households in two village areas. Of these households, 25% contributed 78.1% of An. arabiensis, and households with high frequencies of An. arabiensis were significantly spatially clustered. The results indicate that substantial heterogeneity in malaria risk exists at local and household levels, and household-level heterogeneity may be influenced by interventions, such as ITNs.
authors: W. Harry Feinstone Department of Molecular Microbiology and Immunology, The Johns Hopkins Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA. lcnorris@ucdavis.edu
authors: Laura C
authors: LC
authors: Norris
authors: Douglas E
authors: DE
authors: Norris
mesh_terms: D000483:Alleles; D000818:Animals; D000852:Anopheles / Q000469:parasitology / Q000502:physiology*; D005191:Family Characteristics; D005247:Feeding Behavior / Q000502:physiology*; D005260:Female; D015894:Genome, Human; D060005:Genotyping Techniques; D006801:Humans; D007299:Insect Bites and Stings / Q000517:prevention & control*; D007303:Insect Vectors / Q000469:parasitology / Q000502:physiology*; D057148:Insecticide-Treated Bednets; D008288:Malaria / Q000517:prevention & control*; D008297:Male; D018895:Microsatellite Repeats; D009032:Mosquito Control / Q000379:methods*; D011156:Population Density; D012307:Risk Factors; D012621:Seasons; D012737:Sex Factors; D015024:Zambia
references: Int J Health Geogr. 2010 Nov 05;9:58
references: 21050496
references: Am J Trop Med Hyg. 2010 Jul;83(1):33-7
references: 20595474
references: Methods Mol Med. 2002;72:3-11
references: 12125127
references: Proc Natl Acad Sci U S A. 1997 Jan 7;94(1):338-42
references: 8990210
references: Stat Med. 2006 Nov 30;25(22):3929-43
references: 16435334
references: Vector Borne Zoonotic Dis. 2011 Aug;11(8):1173-9
references: 21142969
references: Am J Trop Med Hyg. 1993 Oct;49(4):520-9
references: 8214283
references: Am J Trop Med Hyg. 2007 Feb;76(2):267-74
references: 17297034
references: Proc Biol Sci. 1998 May 7;265(1398):763-8
references: 9628035
references: Am J Trop Med Hyg. 2010 Oct;83(4):838-42
references: 20889876
references: Int J Legal Med. 1994;106(4):190-3
references: 8038111
references: Parasitol Today. 2000 Feb;16(2):74-7
references: 10652493
references: Am J Trop Med Hyg. 2006 Aug;75(2):231-7
references: 16896124
references: Am J Trop Med Hyg. 1991 Nov;45(5):587-92
references: 1951868
references: Malar J. 2011 Aug 31;10:254
references: 21880143
references: Am J Trop Med Hyg. 2005 Aug;73(2):336-42
references: 16103600
references: Am J Trop Med Hyg. 2008 Dec;79(6):876-80
references: 19052296
references: Acta Trop. 1995 Mar;59(1):1-18
references: 7785522
references: Malar J. 2011 Jun 10;10:163
references: 21663661
references: J Med Entomol. 1993 Mar;30(2):368-73
references: 8459413
references: PLoS Biol. 2007 Mar;5(3):e42
references: 17311470
references: Trans R Soc Trop Med Hyg. 1986;80(1):69-77
references: 3727001
references: J Am Mosq Control Assoc. 1988 Dec;4(4):536-8
references: 3066845
references: Am J Trop Med Hyg. 2010 Oct;83(4):848-53
references: 20889878