August 19th marks World Humanitarian Day – a UN initiative to “honor those who step into crises to help others, and to stand with the millions of people whose lives hang in the balance.”

This year’s campaign aims to highlight a humanitarian system that is stretched to its limits; underfunded, overwhelmed and under attack. In this special blog post, Dr Anna Conzatti, explores an often overlooked factor related to these trends – the impact emergency shelters can have on health.

Every year, millions of people are forced to leave their homes due to conflict, disasters, or climate change. For them, shelter is more than a roof over their heads – it is a foundation for survival, dignity, and recovery. Yet, too often, humanitarian shelters are treated as short-term solutions, overlooking their long-term impact on the health and wellbeing of displaced populations.

Shelter as a health determinant

My doctoral research investigated how the design of humanitarian shelters influences indoor environmental quality – particularly ventilation, thermal comfort, and air quality – and how these factors affect health. Inadequate ventilation can increase the spread of airborne diseases, such as tuberculosis and COVID-19, while poor thermal conditions can cause heat stress or exacerbate respiratory illnesses.

In many displacement contexts, shelters are built quickly, with limited materials, and designed for climates that differ from where they are deployed. The result can be overcrowded, poorly ventilated, and thermally uncomfortable living spaces – conditions that compromise both physical and mental health.

From research to practice

During my PhD, I developed SheltAir, a modelling tool to help shelter designers predict indoor air quality and ventilation performance, taking into account local climate and disease transmission risks. This tool is currently being tested in real-world humanitarian settings, including Afghanistan and Gaza, to evaluate its effectiveness and adaptability.

Recent global events – from the protracted Syrian crisis to rapid-onset disasters in the Horn of Africa – have highlighted the urgent need for evidence-based shelter design. New research emphasises that climate change will intensify displacement while also exposing displaced populations to more extreme temperatures, higher humidity, and air pollution. Integrating climate-responsive design principles is no longer optional, it is essential for protecting health.

The road ahead

The humanitarian sector is increasingly recognising the role of shelter in health outcomes. Initiatives are emerging to integrate health indicators into shelter assessments, apply low-cost monitoring technologies, and involve displaced communities in co-design processes. These steps not only improve shelter performance but also empower communities to shape their living environments.

However, significant challenges remain. Funding cycles often prioritise immediate needs over long-term health benefits. Supply chains still rely on one-size-fits-all shelter kits that may not suit local climates. And while humanitarian standards acknowledge the importance of indoor environmental quality, their application in the field is inconsistent.

A call to action

On this World Humanitarian Day, we must reaffirm that shelter is not merely about protection from the elements. It is about enabling people to live, recover, and rebuild in conditions that do not harm their health. This requires collaboration between humanitarian practitioners, engineers, public health experts, and, most importantly, displaced communities themselves.

If we design and deliver shelters with health at the centre, we move closer to humanitarian responses that are truly life-saving in the short term and life-sustaining in the long term.