Necessity of long-term support after disasters: lessons from disaster-related death criteria after the Fukushima nuclear disaster.

As disasters increase in both frequency and complexity, their indirect effects - such as disruptions to medical care, environmental changes, prolonged periods of evacuation, and psychosocial stress - are increasingly recognised as critical public health issues. In Japan, disaster-related deaths (DRDs) represent an institutional framework to address these secondary health impacts. We compare two DRD certification systems: the Nagaoka Criteria and the Minamisoma Criteria. The former employs a strict time-based cutoff, often excluding deaths beyond six months post-disaster, whereas the latter emerged from the Fukushima disaster context and allows for broader, individualised assessments, recognising long-term and indirect health deterioration as disaster-related. These differences highlight the importance of flexible criteria that reflect the realities of prolonged displacement and chronic disease progression. By leveraging DRD data, it is possible to identify populations most vulnerable to secondary health impacts and incorporate these insights into disaster preparedness and health policy. As promoted by the Sendai Framework's 'Build Back Better' principle, revising DRD certification to encompass long-term impacts is essential to reduce preventable disaster-related mortality and strengthen health systems in the aftermath of complex emergencies.