Evolutionary Ecology group, University of Antwerp, Antwerpen, Belgium
Division of Invertebrates, Department of Biology, Royal Museum for Central Africa, Tervuren, Belgium.
BMJ Glob Health. 2024 Oct 22;9(10):e015375. doi: 10.1136/bmjgh-2024-015375.
Despite worldwide efforts to eradicate malaria over the past century, the disease remains a significant challenge in the Democratic Republic of the Congo (DRC) today. Climate change is even anticipated to worsen the situation in areas with higher altitudes and vulnerable populations. This study in Haut-Katanga, a highland region, aims to evaluate the effectiveness of past control measures and to explore the impact of climate change on the region's distinct seasonal malaria pattern throughout the last century.
We integrated colonial medical records (1917-1983) from two major mining companies (Union Minière du Haut-Katanga and the Générale des Carrières et des Mines) with contemporary data (2003-2020) from Lubumbashi. Concurrently, we combined colonial climate records (1912-1946) with recent data from satellite images and weather stations (1940-2023). We used Generalised Additive Models to link the two data sources and to test for changing seasonal patterns in transmission.
Malaria transmission in Haut-Katanga has fluctuated significantly over the past century, influenced by evolving control strategies, political conditions and a changing climate. A notable decrease in cases followed the introduction of dichlorodiphenyltrichloroethane (DDT), while a surge occurred after the civil wars ended at the beginning of the new millennium. Recently, the malaria season began 1-2 months earlier than historically observed, likely due to a 2-5°C increase in mean minimum temperatures, which facilitates the sporogonic cycle of the parasite.
Despite contemporary control efforts, malaria incidence in Haut-Katanga is similar to levels observed in the 1930s, possibly influenced by climate change creating optimal conditions for malaria transmission. Our historical data shows that the lowest malaria incidence occurred during periods of intensive DDT use and indoor residual spraying. Consequently, we recommend the systematic reduction of vector populations as a key component of malaria control strategies in highland regions of sub-Saharan Africa.
尽管过去一个世纪以来，全球范围内都在努力消灭疟疾，但该疾病在刚果民主共和国（DRC）至今仍是一个重大挑战。气候变化甚至预计会使高海拔和脆弱人群地区的情况恶化。本研究位于上开赛省，一个高原地区，旨在评估过去控制措施的有效性，并探索气候变化对该地区过去一个世纪独特季节性疟疾模式的影响。
我们整合了两家主要矿业公司（Union Minière du Haut-Katanga 和 Générale des Carrières et des Mines）的殖民时期医疗记录（1917-1983 年）和卢本巴希的当代数据（2003-2020 年）。同时，我们将殖民时期的气候记录（1912-1946 年）与卫星图像和气象站的近期数据（1940-2023 年）相结合。我们使用广义加性模型将这两个数据源联系起来，并测试传播的季节性模式变化。
过去一个世纪，上开赛省的疟疾传播情况波动明显，受到不断变化的控制策略、政治条件和气候变化的影响。滴滴涕（DDT）的引入导致病例数量显著下降，而新千年初内战结束后病例数量又出现激增。最近，疟疾季节比历史上观察到的提前了 1-2 个月开始，可能是由于平均最低气温升高了 2-5°C，这有利于寄生虫的孢子生殖周期。
尽管采取了当代控制措施，上开赛省的疟疾发病率与 20 世纪 30 年代观察到的水平相似，可能受到气候变化的影响，这种变化为疟疾传播创造了最佳条件。我们的历史数据表明，在滴滴涕使用和室内滞留喷洒密集时期，疟疾发病率最低。因此，我们建议系统地减少蚊子种群作为撒哈拉以南非洲高地地区疟疾控制策略的一个关键组成部分。
