Maharaj Rajendra, Abdelatif Nada, Maquina Mara, Seocharan Ishen, Lakan Vishan, Paaijmans Krijn, Maartens Francois, Aide Pedro, Sauté Francisco
Malaria Research Group, South African Medical Research Council, Durban, South Africa.
Institute for Sustainable Malaria Control, University of Pretoria, Pretoria, South Africa.
Malar J. 2025 Jan 21;24(1):22. doi: 10.1186/s12936-025-05258-0.
Imported malaria from southern Mozambique drives low levels of disease transmission in KwaZulu-Natal, South Africa. Therefore, the South African Department of Health funded implementation of indoor residual spraying (IRS) in Mozambiquan districts identified as sources of malaria infection for border communities in KwaZulu-Natal. IRS was initiated in districts of Guija, Inharrime, Panda and Zavala. To determine impact of spraying on malaria transmission in these districts, data relating to incidence and prevalence was collected before spraying (2018) and before the second round of spraying was completed (2023). Implementation of IRS was also monitored to ensure optimal spray coverage was achieved.
The study was a cross-sectional survey conducted in 6 sentinel sites in each of the four afore-mentioned districts, focusing on children 6 months to < 15 years from selected households. There was a baseline and an endline cross-sectional survey. Baseline prevalence took place during March-April 2022 whereas the endline surveys occurred during February-March 2023. One hundred and twenty children from each sentinel site were tested for malaria using rapid diagnostic tests. Monthly malaria cases were obtained from health facilities in each study district. Spray data was obtained from LSDI2 initiative who implemented IRS in the targeted districts.
The study showed a definite impact of IRS on malaria prevalence in the targeted districts. Prevalence for sentinel sites in Guija district indicated that the prevalence of malaria increased slightly from baseline to endline in all sentinel sites in Guija. Overall, there was no significant change in prevalence in Zavala, from baseline to endline (p-value = 0.611). Panda's overall malaria prevalence decreased from 19.20% to 10.82% (p-value < 0.001) whereas overall prevalence in Inharrime, decreased from 27.68% to 19.50% (p-value < 0.001). Malaria prevalence in children younger than 5 years decreased significantly in all four districts. In Panda there was a decrease in numbers of males and females being infected between surveys (p < 0.001), whereas for Inharrime the decrease was significant in females (p < 0.001). High coverage with IRS (> 95%) resulted in greater population protection.
The study revealed that IRS implementation decreased malaria prevalence in Inharrime and Panda but not in Guija and Zavala. To ensure that cross-border movement of people does not result in increased malaria transmission, targeting areas identified as source of infection in travelers is paramount to reaching elimination.
莫桑比克南部输入的疟疾导致南非夸祖鲁 - 纳塔尔省的疾病传播水平较低。因此，南非卫生部资助在被确定为夸祖鲁 - 纳塔尔省边境社区疟疾感染源的莫桑比克各地区实施室内滞留喷洒（IRS）。IRS在吉亚、伊纳里梅、潘达和扎瓦拉等地区启动。为了确定喷洒对这些地区疟疾传播的影响，收集了喷洒前（2018年）和第二轮喷洒完成前（2023年）与发病率和患病率相关的数据。还对IRS的实施情况进行了监测，以确保实现最佳喷洒覆盖率。
该研究是在上述四个地区的每个地区的6个哨点进行的横断面调查，重点关注来自选定家庭的6个月至未满15岁的儿童。有一次基线横断面调查和一次终线横断面调查。基线患病率调查于2022年3月至4月进行，而终线调查于2023年2月至3月进行。每个哨点的120名儿童使用快速诊断检测进行疟疾检测。每月疟疾病例从每个研究地区的卫生设施获取。喷洒数据从在目标地区实施IRS的LSDI2倡议中获得。
该研究表明IRS对目标地区的疟疾患病率有明确影响。吉亚地区哨点的患病率表明，吉亚所有哨点的疟疾患病率从基线到终线略有上升。总体而言，扎瓦拉的患病率从基线到终线没有显著变化（p值 = 0.611）。潘达的总体疟疾患病率从19.20%降至10.82%（p值 < 0.001），而伊纳里梅的总体患病率从27.68%降至19.50%（p值 < 0.001）。所有四个地区5岁以下儿童的疟疾患病率均显著下降。在潘达，两次调查之间感染的男性和女性数量有所减少（p < 0.001），而在伊纳里梅，女性的下降幅度显著（p < 0.001）。IRS高覆盖率（> 95%）带来了更大的人群保护。
该研究表明，实施IRS降低了伊纳里梅和潘达的疟疾患病率，但在吉亚和扎瓦拉没有降低。为确保人员跨境流动不会导致疟疾传播增加，将被确定为旅行者感染源的地区作为目标对于实现消除疟疾至关重要。
