Spatio-temporal distribution of malaria and its association with climatic factors and vector-control interventions in two high-risk districts of Nepal

Malaria Journal

Research

Robert B O’Hara¹  Bodo Ahrens²  Ramchandra Karki³  Ulrich Kuch⁴  Garib D Thakur⁵  Meghnath Dhimal⁶ 

[1] Biodiversity and Climate Research Centre (BiK-F), Senckenberg Gesellschaft für Naturforschung, Frankfurt am Main, Germany;Biodiversity and Climate Research Centre (BiK-F), Senckenberg Gesellschaft für Naturforschung, Frankfurt am Main, Germany;Institute for Atmospheric and Environmental Sciences (IAU), Goethe University, Frankfurt am Main, Germany;Department of Hydrology and Meteorology (DHM), Ministry of Science, Technology and Environment, Kathmandu, Babar Mahal, Nepal;Institute of Occupational Medicine, Social Medicine and Environmental Medicine, Goethe University, Frankfurt am Main, Germany;Ministry of Health and Population (MoHP), Government of Nepal, Kathmandu, Ramshah Path, Nepal;Nepal Health Research Council (NHRC), Ministry of Health and Population Complex, Kathmandu, Ramshah Path, Nepal;Biodiversity and Climate Research Centre (BiK-F), Senckenberg Gesellschaft für Naturforschung, Frankfurt am Main, Germany;Institute for Atmospheric and Environmental Sciences (IAU), Goethe University, Frankfurt am Main, Germany;Institute of Occupational Medicine, Social Medicine and Environmental Medicine, Goethe University, Frankfurt am Main, Germany;

关键词: Climate change;    Cross-border;    Hotspots;    Imported malaria;    Insecticide-treated nets;    Indoor residual spraying;    Jhapa;    Minimum temperature;    Morang;    Relative humidity;   

DOI  :  10.1186/1475-2875-13-457

 received in 2014-10-07, accepted in 2014-11-19,  发布年份 2014

来源: Springer

【 摘 要 】

BackgroundOver the last decade, the incidence of confirmed malaria has declined significantly in Nepal. The aim of this paper is to assess the spatio-temporal distribution of malaria and its association with climatic factors and vector control interventions in two high-risk districts of Nepal.MethodsHotspot analysis was used to visualize the spatio-temporal variation of malaria incidence over the years at village level and generalized additive mixed models were fitted to assess the association of malaria incidence with climatic variables and vector control interventions.ResultsOpposing trends of malaria incidence were observed in two high-risk malaria districts of eastern and far-western Nepal after the introduction of long-lasting insecticidal nets (LLINs). The confirmed malaria incidence was reduced from 2.24 per 10,000 in 2007 to 0.31 per 10,000 population in 2011 in Morang district but increased from 3.38 to 8.29 per 10,000 population in Kailali district. Malaria hotspots persisted mostly in the same villages of Kailali district, whereas in Morang district malaria hotspots shifted to new villages after the introduction of LLINs. A 1° C increase in minimum and mean temperatures increased malaria incidence by 27% (RR =1.27, 95% CI =1.12-1.45) and 25% (RR =1.25, 95% CI =1.11-1.43), respectively. The reduction in malaria incidence was 25% per one unit increase of LLINs (RR =0.75, 95% CI =0.62-0.92). The incidence of malaria was 82% lower in Morang than in Kailali district (RR =0.18, 95% CI =0.11-0.33).ConclusionsThe study findings suggest that LLIN coverage should be scaled up to entire districts rather than high-incidence foci only. Climatic factors should be considered for malaria micro-stratification, mosquito repellents should be prescribed for those living in forests, forest fringe and foothills and have regular visits to forests, and imported cases should be controlled by establishing fever check posts at border crossings.

【 授权许可】

CC BY   
© Dhimal et al.; licensee BioMed Central Ltd. 2014