Journal of Mosquito Research 2024, Vol.14, No.2, 100-110 http://emtoscipublisher.com/index.php/jmr 104 gravid Anopheles arabiensis mosquitoes further linking rice cultivation to increased mosquito populations (Wondwosen et al., 2016). 4.1.2 Impact on local mosquito populations and disease transmission The impact of rice cultivation on local mosquito populations and malaria transmission is profound. The stable aquatic conditions in rice fields can lead to a significant increase in mosquito vector populations thereby elevating the risk of malaria transmission. A systematic review and meta-analysis highlighted that rice fields are capable of generating large numbers of malaria vectors contributing to over 400,000 malaria-related deaths annually worldwide (Chan et al., 2022), Moreover the presence of rice fields has been associated with higher malaria incidence rates in surrounding communities as observed in Malanville where malaria cases peaked during the rice production season (Djégbe et al., 2020). 4.2 Case study 2: irrigation systems in Sub-Saharan Africa 4.2.1 Role of irrigation in altering mosquito habitats Irrigation systems in Sub-Saharan Africa significantly alter mosquito habitats by creating numerous breeding sites for malaria vectors. In Western Kenya irrigated ecosystems were found to have a three-fold increase in suitable mosquito breeding habitats compared to non-irrigated areas leading to higher larval densities and increased production of adult mosquitoes (Orondo et al., 2022), Similarly irrigation in Homa Bay and Kisumu Counties Kenya was associated with a more than two-fold increase in Plasmodium infection prevalence and a three-fold increase in clinical malaria incidence compared to non-irrigated areas (Zhou et al., 2022). Zhou et al. (2022) effectively demonstrated the differences in malaria incidence between irrigated and non-irrigated areas, showing consistently higher incidence rates in irrigated regions (Figure 1). The visual representation in the figure highlights the close relationship between irrigation practices and malaria transmission dynamics, making it an important reference case for understanding the impact of irrigation systems on mosquito habitats in sub-Saharan Africa. Figure 1 Active case surveillance in Homa Bay: (A) biweekly dynamics of clinical malaria incidence (cases/1000 people/month) in the irrigated and nonirrigated areas, with shaded areas representing 95% confidence intervals; and (B) distribution of average clinical incidence in each study cluster. Each dot represents 1 cluster (Adopted from Zhou et al., 2022) 4.2.2 Community responses and mitigation strategies Communities in Sub-Saharan Africa have adopted various strategies to mitigate the impact of irrigation on mosquito populations and malaria transmission. Effective water management practices such as intermittent irrigation have been shown to reduce the abundance of malaria vectors. For example intermittent irrigation in rice fields can reduce the abundance of late-stage anopheline larvae by 35% compared to continuous flooding (Chan et al., 2022), Additionally incorporating larval source management into routine malaria control strategies has been
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