In the past decade, flooding took place in 50 of 53 countries in the WHO European region, with the most severe floods in Romania, Russia, Turkey, and the UK. It is projected that flooding could affect 250 000–400 000 additional people across Europe by the 2080s with the UK and central Europe among the most severely affected.
More than 1000 people were killed by floods and 5-6 million more affected in Europe in the past 10 years alone. As climate change progresses, flooding events are expected to increase in frequency and intensity due to rising sea levels and more frequent and extreme precipitation events, and increased urbanization will expose more people.
The characteristics of floods and their impact on human health have been examined in epidemiological studies from both high-income and low-income countries. Immediate effects of flooding are usually due to drowning, injuries, infections, chemical hazards, and disruption to health services, but the longer term effects are less well understood. In high-income countries, floods cause few deaths; however, mental health problems are estimated to account for 80% of all disability adjusted life-years attributable to floods in the UK.
A systematic mapping review suggested a shortage of research into the mental health effects of fluvial (river) flooding, compared with coastal flooding or tsunami-related or hurricane-related flooding. Therefore, improvement of the understanding of longer-term health effects of flooding and effective methods to mitigate these effects are needed.

In their study in The Lancet Planetary Health, Alice Munro and colleagues address this knowledge gap by using a subset of the data from the UK National Study of Flooding and Health to investigate whether evacuation or displacement were associated with poorer mental health than flooding without evacuation or displacement. Munro and colleagues report a significant association between displacement after the 2013–14 floods and the prevalence of symptoms of depression, anxiety, and post-traumatic stress disorder 1 year after the event. They also found that an increased amount of warning received was protective.
As climate change progresses, attention to public health consequences of extreme weather events and mechanisms to tackle them is urgently needed.