Scientists highlight that actions that address environmental protection and climate change can also help with reducing infectious disease threats. Results using data from a national sample survey in New Zealand indicate that perceptions of co-benefits of actions to address environmental protection that also protect against infectious disease outbreaks such as the coronavirus is associated with policy support and political engagement. This association was partly mediated through perceived collective efficacy. Local councils with higher level of community collective efficacy were more likely to declare climate emergency. Communication about potential co-benefits is likely to shape public engagement and enact policy change.