Background: In public health emergencies, evidence, intervention, decisions and translation proceed simultaneously, in greatly compressed timeframes, with knowledge and advice constantly in flux. Idealised approaches to evidence-based policy and practice are ill equipped to deal with the uncertainties arising in evolving situations of need. Key points for discussion: There is much to learn from rapid assessment and outbreak science approaches. These emphasise methodological pluralism, adaptive knowledge generation, intervention pragmatism, and an understanding of health and intervention as situated in their practices of implementation. The unprecedented challenges of novel viral outbreaks like COVID19 do not simply require us to speed up existing evidence-based approaches, but necessitate new ways of thinking about how a more emergent and adaptive evidence-making might be done. The COVID-19 pandemic requires us to appraise critically what constitutes 'evidence-enough' for iterative rapid decisions in-the-now. There are important lessons for how evidence and intervention co-emerge in social practices, and for how evidence-making and intervening proceeds through dialogue incorporating multiple forms of evidence and expertise. Conclusions and implications: Rather than treating adaptive evidence-making and decision making as a break from the routine, we argue that this should be a defining feature of an 'evidence-making intervention' approach to health.