Aregawi Maru W, Maiteki Catherine, Rek John C, Agaba Bosco, Katureebe Charles, Ranjbar Mansour, Zhang Chunzhe, Kiware Samson, Opigo Jimmy
Global Malaria Programme, Universal Health Coverage/Communicable and Non-Communicable Diseases (UCN) Division, World Health Organization, Geneva, Switzerland.
Ministry of Health, Kampala, Uganda.
Malar J. 2025 Jul 17;24(1):235. doi: 10.1186/s12936-025-05351-4.
In Uganda, malaria is a year-round health threat, with transmission intensity varying across regions. Despite ongoing intensified interventions, an unprecedented malaria resurgence in early 2022 affected several districts, prompting a swift response from the National Malaria Control Division (NMCD). This study aims to assess the scale and underlying causes of the epidemics, quantify the excess cases and deaths, and propose targeted prevention and response strategies.
District Health Information System (DHIS2) data from 2017 to 2022 were analysed. A 75th percentile threshold from 2017 to 2021 was used to define true malaria epidemics and compare them to the suspected 2022 epidemic. Excess cases, admissions, and deaths were quantified using area under the curve (AUC) calculations. The level of epidemics was compared across districts with Indoor Residual Spraying (IRS) and Integrated Community Case Management (iCCM) interventions. Precipitation data from multiple sources were used to evaluate rainfall patterns and their impact on malaria epidemics.
Malaria cases were lowest in 2018 but rose by 31% in 2022 compared to the 2017-2021 3rd quartile. Sixty-four of 146 districts experienced epidemics, with 4 facing persistent epidemics year-round. The 2022 epidemic accounted for 3,379,309 (95% CI 1,553,714, 5,339,709) total excess outpatient malaria cases (confirmed and presumed), 3,018,920 (95% CI 1,321,951, 4,661,201) excess confirmed cases, 149,789 (95% CI 66,029, 235,743) excess inpatient cases. Paradoxically, more epidemics occurred in IRS and iCCM districts. Precipitation patterns were consistent across years and were insignificantly correlated with the 2022 epidemic. Provinces with bimodal rainfall patterns were more prone to epidemics, while unimodal regions had fewer epidemics but higher incidence rates. Rainfall lagged by two months (Lag 2) significantly increased malaria incidence (p < 0.01), with each millimetre of rainfall two months prior associated with 13.4 additional malaria cases.
The 2022 malaria epidemic affected 64 districts, with over 3.3 million excess cases and nearly 150,000 excess admissions. Gaps in IRS, iCCM, and intervention coverage, along with minimal rainfall correlation and high vulnerability in bimodal regions, highlight the need for better surveillance, sustainable funding, and tailored responses. While climate was not the main driver, programmatic deficiencies, vector composition shift, reduced efficacy of insecticides, coverage and effectiveness of the interventions likely fueled the epidemic. Strengthening epidemic preparedness, response, and investment will be crucial to preventing future outbreaks and achieving long-term malaria control in Uganda.
在乌干达，疟疾是全年的健康威胁，不同地区的传播强度各异。尽管持续加强干预措施，但2022年初前所未有的疟疾疫情卷土重来，影响了多个地区，促使国家疟疾控制司（NMCD）迅速做出反应。本研究旨在评估疫情的规模和潜在原因，量化额外的病例和死亡人数，并提出有针对性的预防和应对策略。
分析了2017年至2022年的地区卫生信息系统（DHIS2）数据。使用2017年至2021年的第75百分位数阈值来定义真正的疟疾疫情，并将其与2022年疑似疫情进行比较。使用曲线下面积（AUC）计算来量化额外的病例、住院人数和死亡人数。比较了采用室内滞留喷洒（IRS）和综合社区病例管理（iCCM）干预措施的地区的疫情水平。使用多个来源的降水数据来评估降雨模式及其对疟疾疫情的影响。
2018年疟疾病例数最低，但与2017 - 2021年第三四分位数相比，2022年上升了31%。146个地区中有64个经历了疫情，其中4个地区全年疫情持续。2022年的疫情导致总计3379309例（95%置信区间1553714, 5339709）额外的门诊疟疾病例（确诊和疑似），3018920例（95%置信区间1321951, 4661201）额外的确诊病例，149789例（95%置信区间66029, 235743）额外的住院病例。矛盾的是，采用IRS和iCCM的地区出现了更多疫情。多年来降水模式一致，与2022年疫情的相关性不显著。有双峰降雨模式的省份更容易发生疫情，而单峰地区疫情较少但发病率较高。滞后两个月（滞后2）的降雨显著增加了疟疾发病率（p < 0.01），前两个月每毫米降雨与额外13.4例疟疾病例相关。
2022年的疟疾疫情影响了64个地区（县），有超过330万例额外病例和近15万例额外住院病例。IRS、iCCM及干预措施覆盖方面存在差距，降雨相关性极小以及双峰地区的高度脆弱性，凸显了加强监测、可持续资金投入和针对性应对措施的必要性。虽然气候不是主要驱动因素，但项目缺陷、病媒构成变化、杀虫剂效力降低、干预措施的覆盖范围和效果可能助长了疫情。加强疫情防范、应对和投资对于预防未来疫情爆发以及在乌干达实现长期疟疾控制至关重要。
