Systematic review of Aedes aegypti control trials suggests publication bias related to author disclosure of conflicts of interest

BACKGROUND: Aedes aegypti mosquitoes transmit multiple arboviruses, including dengue, Zika, chikungunya, and yellow fever, resulting in a large global disease burden. Vector control remains the key strategy to prevent transmission due to the absence of widely available vaccines or treatments. Many studies evaluate control approaches, yet only a subset are published in peer-reviewed journals. One potential contributor to selective reporting, or publication bias, could be a conflict of interest (COI), defined as employment by a for-profit company conducting the trial, or a financial interest tied to the tool's intellectual property. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a systematic literature review of Ae. aegypti control trials from 2010 to 2022 to test the hypothesis that published trials with author-declared COI report a higher average level of Ae. aegypti suppression than publications whose authors declare no COI. Inclusion criteria required entomological outcomes (adult abundance or immature indices) with baseline and post-intervention data for both treated and untreated areas. Studies limited to laboratory, semi-field, or virus-only outcomes were excluded. We identified 51 publications that met the inclusion criteria. The studies with declared COI reported a 56.7% reduction in Ae. aegypti population, significantly higher than the 34.5% reduction in studies declaring no COI. The 51 studies were published in 26 different journals and eight (30.7%) did not have standard publishing policies that include the reporting of authors' COI statements in the published articles. CONCLUSIONS/SIGNIFICANCE: Our findings suggest that author-reported COI is associated with higher mosquito population suppression. This association may reflect the use of more effective interventions in COI-affiliated studies or publication bias. We also observed inconsistencies in COI policies and the display of COI statements across journals, underscoring the need for standardized and transparent reporting.