Wolbachia‐carrying Aedes mosquitoes for preventing dengue infection

Background Dengue is a global health problem of high significance, with 3.9 billion people at risk of infection. The geographic expansion of dengue virus (DENV) infection has resulted in increased frequency and severity of the disease, and the number of deaths has increased in recent years. Wolbachia, an intracellular bacterial endosymbiont, has been under investigation for several years as a novel dengue‐control strategy. Some dengue vectors (Aedes mosquitoes) can be transinfected with specific strains of Wolbachia, which decreases their fitness (ability to survive and mate) and their ability to reproduce, inhibiting the replication of dengue. Both laboratory and field studies have demonstrated the potential effect of Wolbachia deployments on reducing dengue transmission, and modelling studies have suggested that this may be a self‐sustaining strategy for dengue prevention, although long‐term effects are yet to be elucidated. Objectives To assess the efficacy of Wolbachia‐carrying Aedes species deployments (specifically wMel‐, wMelPop‐, and wAlbB‐ strains of Wolbachia) for preventing dengue virus infection. Search methods We searched CENTRAL, MEDLINE, Embase, four other databases, and two trial registries up to 24 January 2024. Selection criteria Randomized controlled trials (RCTs), including cluster‐randomized controlled trials (cRCTs), conducted in dengue endemic or epidemic‐prone settings were eligible. We sought studies that investigated the impact of Wolbachia‐carrying Aedes deployments on epidemiological or entomological dengue‐related outcomes, utilizing either the population replacement or population suppression strategy. Data collection and analysis Two review authors independently selected eligible studies, extracted data, and assessed the risk of bias using the Cochrane RoB 2 tool. We used odds ratios (OR) with the corresponding 95% confidence intervals (CI) as the effect measure for dichotomous outcomes. For count/rate outcomes, we planned to use the rate ratio with 95% CI as the effect measure. We used adjusted measures of effect for cRCTs. We assessed the certainty of evidence using GRADE. Main results One completed cRCT met our inclusion criteria, and we identified two further ongoing cRCTs. The included trial was conducted in an urban setting in Yogyakarta, Indonesia. It utilized a nested test‐negative study design, whereby all participants aged three to 45 years who presented at healthcare centres with a fever were enrolled in the study p