College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda.
Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Stellenbosch, South Africa.
BMC Infect Dis. 2020 Jun 17;20(1):425. doi: 10.1186/s12879-020-05158-5.
Malaria remains a major tropical vector-borne disease of immense public health concern owing to its debilitating effects in sub-Saharan Africa. Over the past 30 years, the high altitude areas in Eastern Africa have been reported to experience increased cases of malaria. Governments including that of the Republic of Uganda have responded through intensifying programs that can potentially minimize malaria transmission while reducing associated fatalities. However, malaria patterns following these intensified control and prevention interventions in the changing climate remains widely unexplored in East African highland regions. This study thus analyzed malaria patterns across altitudinal zones of Mount Elgon, Uganda.
Times-series data on malaria cases (2011-2017) from five level III local health centers occurring across three altitudinal zones; low, mid and high altitude was utilized. Inverse Distance Weighted (IDW) interpolation regression and Mann Kendall trend test were used to analyze malaria patterns. Vegetation attributes from the three altitudinal zones were analyzed using Normalized Difference Vegetation Index (NDVI) was used to determine the Autoregressive Integrated Moving Average (ARIMA) model was used to project malaria patterns for a 7 year period.
Malaria across the three zones declined over the study period. The hotspots for malaria were highly variable over time in all the three zones. Rainfall played a significant role in influencing malaria burdens across the three zones. Vegetation had a significant influence on malaria in the higher altitudes. Meanwhile, in the lower altitude, human population had a significant positive correlation with malaria cases.
Despite observed decline in malaria cases across the three altitudinal zones, the high altitude zone became a malaria hotspot as cases variably occurred in the zone. Rainfall played the biggest role in malaria trends. Human population appeared to influence malaria incidences in the low altitude areas partly due to population concentration in this zone. Malaria control interventions ought to be strengthened and strategically designed to achieve no malaria cases across all the altitudinal zones. Integration of climate information within malaria interventions can also strengthen eradication strategies of malaria in such differentiated altitudinal zones.
疟疾仍然是一个主要的热带病，由于其在撒哈拉以南非洲的衰弱影响，引起了极大的公共卫生关注。在过去的 30 年中，据报道东非的高海拔地区疟疾病例有所增加。包括乌干达共和国在内的各国政府通过加强计划做出了回应，这些计划有可能在减少相关死亡人数的同时最大限度地减少疟疾传播。然而，在气候变化的背景下，这些强化控制和预防干预措施之后的疟疾模式在东非高地地区仍未得到广泛探索。因此，本研究分析了乌干达埃尔贡山不同海拔地区的疟疾模式。
利用来自三个海拔高度区（低海拔、中海拔和高海拔）的五个三级地方卫生中心的 2011-2017 年疟疾病例时间序列数据。使用倒数距离加权（IDW）插值回归和曼肯德尔趋势检验来分析疟疾模式。使用归一化差值植被指数（NDVI）分析三个海拔区的植被属性，使用自回归综合移动平均（ARIMA）模型预测 7 年期间的疟疾模式。
三个区的疟疾在研究期间呈下降趋势。在所有三个区，疟疾热点随时间的变化非常大。降雨在三个区的疟疾负担中起着重要作用。植被对高海拔地区的疟疾有重要影响。同时，在低海拔地区，人口与疟疾病例呈显著正相关。
尽管三个海拔区的疟疾病例都有所下降，但由于该区域的病例呈波动变化，高海拔区成为了疟疾热点。降雨对疟疾趋势的影响最大。由于人口集中在该地区，人口似乎在一定程度上影响了低海拔地区的疟疾发病率。需要加强疟疾控制干预措施，并进行战略性设计，以实现所有海拔区都没有疟疾病例。在疟疾干预措施中整合气候信息也可以加强在这些不同海拔区消除疟疾的策略。
