A need for better housing to further reduce indoor malaria transmission in areas with high bed net coverage

Particle and Fibre Toxicology

Silas Majambere¹  Gregor J Devine²  Caroline Harris¹  Stefan Dongus¹  Zawadi D Mageni³  Samson S Kiware⁴  Dickson W Lwetoijera¹ 

[1] Vector Biology Department, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK;Cairns Public Health Unit, Queensland Health, Queensland 4870, Australia;Biomedical and Environmental Thematic Group, Ifakara Health Institute, P.O. Box 53, Ifakara, Tanzania;Department of Mathematics, Statistics and Computer Science, Marquette University, Milwaukee, WI-53201-1881, USA

关键词: Malaria;    ITNs;    Anopheles funestus;    Anopheles gambiae s.l.;    House risk factors;   

Others  :  1228047
DOI  :  10.1186/1756-3305-6-57

 received in 2013-01-17, accepted in 2013-02-26,  发布年份 2013

【 摘 要 】

Background

The suppression of indoor malaria transmission requires additional interventions that complement the use of insecticide treated nets (ITNs) and indoor residual spraying (IRS). Previous studies have examined the impact of house structure on malaria transmission in areas of low transmission. This study was conducted in a high transmission setting and presents further evidence about the association between specific house characteristics and the abundance of endophilic malaria vectors.

Methods

Mosquitoes were sampled using CDC light traps from 72 randomly selected houses in two villages on a monthly basis from 2008 to 2011 in rural Southern Tanzania. Generalized linear models using Poisson distributions were used to analyze the association of house characteristics (eave gaps, wall types, roof types, number of windows, rooms and doors, window screens, house size), number of occupants and ITN usage with mean catches of malaria vectors (An.gambiae s.l. and An. funestus).

Results

A total of 36490 female An. gambiae s.l. were collected in Namwawala village and 21266 in Idete village. As for An. funestus females, 2268 were collected in Namwawala and 3398 in Idete. Individually, each house factor had a statistically significant impact (p < 0.05) on the mean catches for An. gambiae s.l. but not An. funestus. A multivariate analysis indicated that the combined absence or presence of eaves, treated or untreated bed-nets, the number of house occupants, house size, netting over windows, and roof type were significantly related (p < 0.05) to An.gambiae s.l. and An. funestus house entry in both villages.

Conclusions

Despite significant reductions in vector density and malaria transmission caused by high coverage of ITNs, high numbers of host-seeking malaria vectors are still found indoors due to house designs that favour mosquito entry. In addition to ITNs and IRS, significant efforts should focus on improving house design to prevent mosquito entry and eliminate indoor malaria transmission.

【 授权许可】

   
2013 Lwetoijera et al; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

Figure 2.

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