Universidad de San Carlos de Guatemala, Laboratorio de Entomología Aplicada y Parasitología, Ciudad de Guatemala, Guatemala.
Universidad de San Carlos de Guatemala, Facultad de Ciencias Químicas y Farmacia, Escuela de Biología, Ciudad de Guatemala, Guatemala.
Mem Inst Oswaldo Cruz. 2020 Oct 28;115:e200203. doi: 10.1590/0074-02760200203. eCollection 2020.
Deforestation, driven by anthropogenic change in land use, influences the behaviour and abundance of vector-borne diseases. For various species of Chagas disease vectors, there is evidence that change in land use affects population density and abundance. Triatoma dimidiata is the most important Chagas vector in Guatemala, and at least one million people live in T. dimidiata endemic areas; however, infestation dynamics vary among regions, from high infestation with all life stages to low seasonal infestation by sylvatic adults.
The aim of this study was to evaluate how land-use, combined with domiciliary risk factors, influences the infestation dynamics of T. dimidiata for four villages in a dry forest region with a strong deforestation history.
Land use, measured with drone and satellite images, was classified into four categories (houses, monocultures and pastures, woodland and shrubland, and bare soil). Domiciliary risk factors and infestation were assessed through entomological surveys. Statistical analyses compared infestation indices and the ability of land use and domiciliary risk factors to explain infestation.
Two villages had significantly higher infestation (26 and 30% vs. 5 and 6%), yet all villages had high colonisation (71-100% of infested houses had immature insects), with no significant difference among them. Because of the high level of deforestation across the study area, land use was not related to infestation; however, domiciliary risk factors were. A model based on four weighted domiciliary risk factors (adobe or bajareque walls, intradomicile animals, intradomicile clutter, and dirt floors) explains the infestation risk.
Because almost all infested houses have reproducing populations in this deforested dry forest region and statistical analysis identified the domiciliary risk factors for infestation, intermediate and long-term control of Chagas disease vectors in this region requires management of these risk factors.
土地利用的人为变化导致森林砍伐，影响了媒介传播疾病的行为和丰度。对于各种查加斯病媒介物种，有证据表明土地利用的变化会影响其种群密度和丰度。三角锥属 Dimidiata 是危地马拉最重要的查加斯病媒介，至少有 100 万人生活在三角锥属 Dimidiata 流行地区；然而，感染动态因地区而异，从所有生命阶段的高感染到森林成年动物的季节性低感染不等。
本研究旨在评估土地利用与家庭风险因素相结合如何影响一个具有强烈森林砍伐历史的干燥森林地区四个村庄的三角锥属 Dimidiata 的感染动态。
使用无人机和卫星图像测量土地利用，将其分为四类（房屋、单一栽培和牧场、林地和灌木地以及裸地）。通过昆虫学调查评估家庭风险因素和感染情况。统计分析比较了感染指数以及土地利用和家庭风险因素解释感染的能力。
两个村庄的感染率明显更高（26%和 30%对 5%和 6%），但所有村庄的感染率都很高（71%-100%的感染房屋都有未成熟的昆虫），且无显著差异。由于研究区域的森林砍伐率很高，土地利用与感染无关；然而，家庭风险因素是相关的。一个基于四个加权家庭风险因素（土坯或 Bajareque 墙、家庭内动物、家庭内杂物和泥泞的地板）的模型解释了感染风险。
由于在这个森林砍伐的干燥森林地区，几乎所有受感染的房屋都有繁殖种群，并且统计分析确定了感染的家庭风险因素，因此该地区的查加斯病媒介的中期和长期控制需要管理这些风险因素。
