Epidemiology and Diseases Control Section, Ministry of Health, Community Development, Gender, Elderly and Children, Dar es Salaam, Tanzania; Department of Veterinary Medicine and Public Health, Sokoine University of Agriculture, Morogoro, Tanzania; Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway.
Centre for Ecological and Evolutionary Synthesis, University of Oslo, Oslo, Norway.
Int J Infect Dis. 2019 Feb;79:142-151. doi: 10.1016/j.ijid.2018.11.367. Epub 2018 Dec 3.
Anthrax is caused by the spore-forming, Gram-positive bacterium Bacillus anthracis. The aim of this study was to predict the potential distribution of B. anthracis in Tanzania and produce epidemiological evidence for the management of anthrax outbreaks in the country.
The Maxent algorithm was used to predict areas at risk of anthrax outbreaks based on the occurrence and environmental data in Arusha and Kilimanjaro regions; the model was later transferred to predict the entire country. Seventy percent of the occurrence data were used to train the model, while 30% were used for model evaluation.
Four regions of northern Tanzania are predicted to have a high risk for anthrax outbreaks, while the southern and western regions had low-risk areas. Soil type (56.5%), soil pH (23.7%), and isothermally (10.4%) were the most important variables for the model prediction, and the most significant soil types were solonetz, fluvisols, and lithosols.
A strong risk level across districts of the Tanzania mainland was identified in this study. A total of 18 districts in Tanzania Mainland are predicted to be at very high risk of an anthrax outbreak occurrence. These findings are important for policymakers to effectively mount targeted control measures for anthrax outbreaks in Tanzania.
炭疽是由形成孢子的革兰氏阳性细菌炭疽芽孢杆菌引起的。本研究旨在预测坦桑尼亚境内炭疽的潜在分布情况，并为该国炭疽疫情的管理提供流行病学证据。
本研究使用最大熵算法，根据阿鲁沙和乞力马扎罗地区的炭疽发生情况和环境数据，预测炭疽疫情高风险地区；随后，该模型被用于预测整个国家的炭疽疫情。该模型的训练数据为 70%的发生数据，30%的数据用于模型评估。
预测坦桑尼亚北部四个地区炭疽疫情高风险，而南部和西部地区风险较低。土壤类型（56.5%）、土壤 pH 值（23.7%）和等温线（10.4%）是模型预测最重要的变量，最主要的土壤类型是盐沼土、淋溶土和岩成土。
本研究确定了坦桑尼亚大陆各地区炭疽疫情的高风险水平。坦桑尼亚大陆共有 18 个区被预测为炭疽疫情发生的极高风险区。这些发现对决策者在坦桑尼亚有效实施炭疽疫情的针对性控制措施具有重要意义。
