Janko Mark M, Irish Seth R, Reich Brian J, Peterson Marc, Doctor Stephanie M, Mwandagalirwa Melchior Kashamuka, Likwela Joris L, Tshefu Antoinette K, Meshnick Steven R, Emch Michael E
Duke Global Health Institute, Duke University, Durham, NC, USA; Department of Geography, Chapel Hill, NC, USA; Department of Biostatistics, Chapel Hill, NC, USA; Carolina Population Center, Chapel Hill, NC, USA.
University of North Carolina, Chapel Hill, NC, USA; President's Malaria Initiative and Entomology Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA.
Lancet Planet Health. 2018 Feb;2(2):e74-e82. doi: 10.1016/S2542-5196(18)30009-3.
The relationship between agriculture, mosquitoes, and malaria in Africa is not fully understood, but it is important for malaria control as countries consider expanding agricultural projects to address population growth and food demand. Therefore, we aimed to assess the effect of agriculture on biting behaviour and malaria risk in children in rural areas of the Democratic Republic of the Congo (DR Congo).
We did a population-based, cross-sectional, spatial study of rural children (<5 years) in the DR Congo. We used information about the presence of malaria parasites in each child, as determined by PCR analysis of dried-blood spots from the 2013-14 DR Congo Demographic and Health Survey (DHS). We also used data from the DHS, a longitudinal entomological study, and available land cover and climate data to evaluate the relationships between agriculture, biting behaviour, and malaria prevalence. Satellite imagery was used to measure the percentage of agricultural land cover around DHS villages and sites. biting behaviour was assessed by Human Landing Catch. We used probit regression to assess the relationship between agriculture and the probability of malaria infection, as well as the relationship between agriculture and the probability that a mosquito was caught biting indoors.
Between Aug 13, 2013, and Feb 13, 2014, a total of 9790 dried-blood spots were obtained from the DHS, of which 4612 participants were included in this study. Falciparum malaria infection prevalence in rural children was 38·7% (95% uncertainty interval [UI] 37·3-40·0). Increasing exposure to agriculture was associated with increasing malaria risk with a high posterior probability (estimate 0·07, 95% UI -0·04 to 0·17; posterior probability [estimate >0]=0·89), with the probability of malaria infection increased between 0·2% (95% UI -0·1 to 3·4) and 2·6% (-1·5 to 6·6) given a 15% increase in agricultural cover, depending on other risk factors. The models predicted that large increases in agricultural cover (from 0% to 75%) increase the probability of infection by as much as 13·1% (95% UI -7·3 to 28·9). Increased risk might be due to sensu lato, whose probability of biting indoors increased between 11·3% (95% UI -15·3 to 25·6) and 19·7% (-12·1 to 35·9) with a 15% increase in agriculture.
Malaria control programmes must consider the possibility of increased risk due to expanding agriculture. Governments considering initiating large-scale agricultural projects should therefore also consider accompanying additional malaria control measures.
National Institutes of Health, National Science Foundation, Bill & Melinda Gates Foundation, President's Malaria Initiative, and Royster Society of Fellows at the University of North Carolina at Chapel Hill.
非洲农业、蚊子与疟疾之间的关系尚未完全明晰，但鉴于各国考虑扩大农业项目以应对人口增长和粮食需求，这对疟疾防控至关重要。因此，我们旨在评估农业对刚果民主共和国（DR刚果）农村地区儿童叮咬行为和疟疾风险的影响。
我们对DR刚果的农村儿童（<5岁）开展了一项基于人群的横断面空间研究。我们利用了通过对2013 - 14年DR刚果人口与健康调查（DHS）的干血斑进行PCR分析确定的每个儿童体内疟原虫存在情况的信息。我们还使用了DHS的数据、一项纵向昆虫学研究以及现有的土地覆盖和气候数据，以评估农业、叮咬行为和疟疾流行率之间的关系。利用卫星图像测量DHS村庄和地点周围农业土地覆盖的百分比。通过人饵诱捕法评估叮咬行为。我们使用概率回归来评估农业与疟疾感染概率之间的关系，以及农业与蚊子在室内被捕获叮咬概率之间的关系。
在2013年8月13日至2014年2月13日期间，共从DHS获取了9790个干血斑，其中4612名参与者纳入本研究。农村儿童中恶性疟原虫感染率为38.7%（95%不确定区间[UI] 37.3 - 40.0）。农业暴露增加与疟疾风险增加相关，后验概率较高（估计值0.07，95% UI -0.04至0.17；后验概率[估计值>0] = 0.89），在其他风险因素的基础上，农业覆盖增加15%时，疟疾感染概率增加0.2%（95% UI -0.1至3.4）至2.6%（-1.5至6.6）。模型预测农业覆盖大幅增加（从0%至75%）会使感染概率增加多达13.1%（95% UI -7.3至28.9）。风险增加可能归因于广义按蚊，随着农业增加15%，其在室内叮咬的概率增加11.3%（95% UI -15.3至25.6）至19.7%（-12.1至3
