Program in Public Health, College of Health Sciences, University of California at Irvine, Irvine, California, USA.
Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA.
J Infect Dis. 2022 Nov 1;226(9):1657-1666. doi: 10.1093/infdis/jiac361.
Irrigated agriculture enhances food security, but it potentially promotes mosquito-borne disease transmission and affects vector intervention effectiveness. This study was conducted in the irrigated and nonirrigated areas of rural Homa Bay and Kisumu Counties, Kenya.
We performed cross-sectional and longitudinal surveys to determine Plasmodium infection prevalence, clinical malaria incidence, molecular force of infection (molFOI), and multiplicity of infection. We examined the impact of irrigation on the effectiveness of the new interventions.
We found that irrigation was associated with >2-fold higher Plasmodium infection prevalence and 3-fold higher clinical malaria incidence compared to the nonirrigated area. Residents in the irrigated area experienced persistent, low-density parasite infections and higher molFOI. Addition of indoor residual spraying was effective in reducing malaria burden, but the reduction was more pronounced in the nonirrigated area than in the irrigated area.
Our findings collectively suggest that irrigation may sustain and enhance Plasmodium transmission and affects intervention effectiveness.
灌溉农业提高了粮食安全水平，但也可能促进了蚊媒疾病的传播，并影响了病媒干预措施的效果。本研究在肯尼亚霍马贝和基苏木县的农村灌溉区和非灌溉区进行。
我们进行了横断面和纵向调查，以确定疟原虫感染率、临床疟疾发病率、分子感染强度（molFOI）和感染多重性。我们研究了灌溉对新干预措施效果的影响。
与非灌溉区相比，我们发现灌溉与疟原虫感染率高出 2 倍以上和临床疟疾发病率高出 3 倍以上有关。灌溉区的居民经历了持续的低密度寄生虫感染和更高的 molFOI。室内滞留喷洒的增加有效降低了疟疾负担，但在非灌溉区的降低幅度大于灌溉区。
我们的研究结果表明，灌溉可能会维持和增强疟原虫的传播，并影响干预措施的效果。
