Longitudinal Study Analyses Mental Health in Gaza from 2020 to 2025

Since 2019, Swiss TPH has supported the International Committee of the Red Cross (ICRC) in an effort aiming at evidence-based priority setting from a public health perspective in protracted conflict in Gaza. With the outbreak of the war in October 2023, the situation in Gaza changed from protracted conflict to war, resulting in an acute humanitarian crisis. Beyond the physical devastation, the conflict has also had a profound impact on mental health.

A study on mental health in Gaza

Because Swiss TPH and Al Quds University in Gaza had already initiated a population-based study on adult health in 2020 – with baseline data collected before the war – the same participants could be followed up in subsequent years. This made it possible to quantify changes in psychological distress over time, even as the war broke out. 

“In the current humanitarian context, it may seem obvious that people are suffering mentally as well as physically,” said Nicole Probst-Hensch, group leader at Swiss TPH and senior author of the study. “Yet, the purpose of the study was not to state the obvious. It remains essential to build an objective scientific foundation that helps us understand the scale and nature of this distress. Such evidence is crucial for making mental health a central pillar of long-term health and resilience and ensuring mental health interventions are prioritized in recovery planning.” 

Sharp increase of severe distress

The research team tracked 677 adults aged 40 years and older across three survey rounds in 2020, 2023 and 2025. Psychological distress was measured using the General Health Questionnaire (GHQ-12), a validated screening tool widely applied in public health research. 

Findings show that the prevalence of severe psychological distress increased from around 20% before the war to 67% in 2025. Severe psychological distress is a serious health state that requires immediate attention and support. 

“Having baseline data from before the war meant we could follow the same study participants over time and capture how quickly psychological distress escalated,” said Curdin Brugger, Doctoral Candidate at Swiss TPH and first author of the study. “By early 2025, nearly seven in ten participants screened above the threshold for severe distress.” The increase was consistent across men and women as well as socio-demographic subgroups. The findings of the study have been published this week in the peer-reviewed journal eClinicalMedicine.

Importance of local expertise

The study also illustrates the value of long-term collaboration with local experts, which will also remain vital for recovery and rebuilding in Gaza. 

Bassam Abu Hamad, Coordinator of Public Health Programmes at Al Quds University and co-author of the study, highlighted the lived reality behind the numbers: “99% of participants reported at least one displacement and severe disruptions to daily life and services. The distress that we measured reflects a wide-ranging hardship and an alarmingly high level of need for psychological care.”

Insights from rare longitudinal data

Longitudinal data documenting how mental health changes during conflict are very rare. “This is the first study to follow the same individuals in Gaza over several years, offering unique insights for designing context-appropriate mental health responses,” said Probst-Hensch. “Such research in the midst of crisis was only possible through the exceptional commitment of our partners at Al Quds University with whom we had an established long-term partnership.”

From emergency response to recovery

The authors note that while the immediate priority in Gaza is saving lives and restoring basic services, the study also highlights the need to plan for longer-term mental health recovery.

“The findings can help inform recovery planning alongside the restoration of essential services,” said Mirko Winkler, Head of the Urban Public Health unit at Swiss TPH and senior author of the study. “The primary objective of our ICRC mandate in Gaza was priority setting from a public health perspective. This study helps ensure that mental health becomes part of recovery, including psychosocial support and resilience-building – so that future generations have the chance to rebuild their lives, which is essential to putting the conflict aside in the long term.”

The study underlines that sustainable recovery will also depend on empowering local experts and institutions to lead research and rebuilding efforts.

Funding

The health impact assessment of essential services in Gaza was funded through the Resilience Programme of the ICRC. 

Swiss TPH’s work in fragile and conflict-affected settings

Swiss TPH collaborates with national, international and humanitarian partners to provide health system support in crisis contexts and fragile settings. Our projects support evidence generation, capacity strengthening and translating science to impact, with recent activities in Ukraine, Somalia and other fragile regions. In Palestine, Swiss TPH has been active since 2015. 

Swiss TPH’s expertise in mental health

Swiss TPH has long-standing expertise in mental health research, examining how social, environmental and health system factors affect psychological well-being. We conduct population-based studies, validate screening tools and evaluate interventions, generating evidence that informs policies and programmes to improve access to mental health care in stable and crisis-affected settings.