Supplemental Randomization Checks.

<div><p>Climate-facilitated spread of mosquito-borne pathogens to new environments elevates the importance of policies that limit greenhouse gas emissions as well as the development and uptake of new pharmaceutical interventions. Whereas past research attempts to bolster support for both through either climate or health risk communication, fewer attempt to <i>combine</i> the risks borne by climate change <i>and</i> infectious disease with a single messaging intervention, i.e., co-constitutive risk messaging (CCR), a strategy of an integrative approach we call <i>One Health Communication</i>. In a pre-registered experiment embedded in a nationally representative survey (N = 2,200), we test whether CCR messaging impacts support for pharmaceutical interventions to minimize dengue fever health risks and/or policy efforts to mitigate climate change. We find that CCR messages are generally effective at increasing support for pharmaceutical interventions aimed at ameliorating the health risks posed by dengue fever. Moreover, we find suggestive evidence that people who hold more collectivistic worldviews are especially receptive to messages that emphasize the public (vs. the personal) health risks of dengue fever. In <i>post hoc</i> exploratory analyses, we show that CCR messages affect public support for climate change mitigation policies among those who express doubts about human-caused climate change. We conclude by discussing the usefulness of CCR messaging and One Health Communication approaches more broadly in various strategic communication contexts and considering additional avenues for future research.</p></div>