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. Author summary: Many studies evaluate Aedes aegypti mosquito vector control approaches, but only a subset are published. One possible contributor to selective reporting, or publication bias, is the presence of a conflict of interest (COI), such as employment by the company conducting the trial or a financial conflict tied to intellectual property. We conducted a systematic review of field trials of Ae. aegypti control from 2010-2022 and examined whether studies in which authors disclose a COI report higher vector suppression than studies declaring no COI. Among 51 studies that met inclusion criteria, those with declared COI reported greater Ae. aegypti reduction of 56.7% compared to 34.5% from studies that declared no COI. We also observed that COI statements are not consistently published across journals. These findings suggest potential publication bias and underscore the need for consistent, transparent COI disclosure policies to strengthen credibility and interpretation of vector control evidence.