Nearly a quarter of the world’s children are estimated to live in countries affected by armed conflict or disaster. Following Russia’s invasion of Ukraine, the children there are experiencing the devastating consequences of living in a war zone – the constant threat of shelling, shooting and losing loved ones, as well as the worry over accessing food, clean drinking water and healthcare, and the breakdown of their usual routines and structures.

“The legacy of this war will be a traumatized generation,” wrote Serhii Lukashov, the director of SOS Children’s Villages in Ukraine. The mental health impact of this is likely to have consequences for years to come.

Post‐traumatic stress disorder (PTSD) and depression are the most common mental health disorders in the aftermath of war – for both adults and children. While the incidences of these disorders are difficult to estimate, most studies have found significantly raised levels of disturbance compared with control populations. For example, past studies of newly arrived refugee children show rates of anxiety from 49 percent to 69 percent, with prevalence dramatically increasing if at least one parent had been tortured or if families were separated.

PTSD can occur in children after even a single traumatic event, but repeated or prolonged trauma increases the risk. The symptoms of PTSD vary; sufferers may show intense fear, helplessness, anger, sadness, horror or denial. They can also develop physical symptoms including headaches and stomach aches; show more sudden and extreme emotional reactions; or have problems falling or staying asleep. Children who experience repeated trauma may develop a kind of emotional numbing to deaden or block the pain and trauma. This is called dissociation.

Depression can occur in children as young as three years old – they can feel sad or hopeless, or show disinterest in things they used to enjoy. Their sleep patterns and energy levels may change, and some may even self-harm.

How a child’s mental health is affected will depend to a large extent on the support they receive from their caregivers. But this, too, becomes difficult during times of war as normal attachments are frequently disrupted. Some children could lose their caregivers, be separated from them as some members of the family flee and others stay behind to fight, or find that their caregivers are themselves too depressed or anxious or too preoccupied with protecting and finding subsistence for the family to be fully emotionally available.

For children, the detrimental effects of war trauma are not restricted to specific mental health diagnoses but also include a broad and multifaceted set of developmental outcomes that compromise relationships, school performance and general life satisfaction. This is exacerbated by the fact that violent conflict often destroys or significantly damages schools and educational systems. Without the structure offered by schools, children will need the adults in their lives to provide this; we have seen videos online of Ukrainian children in underground bunkers where adults are facilitating lessons and designated playtimes.

It isn’t just loved ones and routines children may be separated from. Many will have to flee their homes at short notice, leaving behind their treasured possessions, such as a specific ‘attachment object’ – usually a favorite blanket or a soft toy. Children often reach for these things when they need to feel safe. But during war, when children are forced to flee and need these objects more than ever, many are left without them.