Abstract
Researchers have long identified the ability of secondary stressors to have impacts on people's wellbeing and mental health that are similar to the direct effects of major incidents (e.g., emergencies, disasters, infectious disease outbreaks, and conflicts) experientially, and in respect of their prevalence and the strain on services. But there is a lack of clarity about the nature of secondary stressors that can hinder efforts to mitigate their effects. We develop a new theoretical approach in this article. We argue that most secondary stressors are a function of: 1. Social factors and people's life circumstances (that include the policies, practices, and social, organisational, and financial arrangements) that exist prior to and impact them during the major incident; and/or 2. Societal and organisational responses to an incident or emergency. We show that this conceptual framework makes sense of the evidence from different domains and represents a more coherent approach than do previous definitions. We present a worked example from our research on the psychosocial effects on healthcare staff of the COVID-19 pandemic that was declared by the World Health Organization in 2020. We argue that our social model enables a holistic approach to conceptualising and intervening to remedy many of the longer-term and widespread negative psychosocial effects of disasters, conflicts and infectious diseases.