MONTSERRADO: Sitting in a dusty schoolyard in rural Liberia, mental health clinician Dickson Korfeh watches as pupils dance, sing and play games in their break, and focuses on those who do not take part.

He frowns as he studies their body language and behaviour for signs of grief and trauma, common in a nation haunted by a 14-year civil war and devastated by Ebola - and with one-tenth of the population suffering from mental illness.

"There is a sadness in schools as pupils have lost family and friends to Ebola... some are suffering from depression or post-traumatic stress disorder (PTSD)," the former nurse said.

"But children do not have the vocabulary to express their suffering, so we analyse the way they act, to look for clues."

Korfeh is one of more than 150 newly trained mental health clinicians in a country that spends less than one percent of its health budget on mental health, a neglected and stigmatised part of a fragile and under-resourced health system.

The 1989-2003 civil war left almost half the population with symptoms of PTSD or depression and created a mental health crisis which was deepened by the Ebola epidemic, experts say.

"Both crises saw bodies pile up in the streets and people flee in panic," said Janice Cooper of the Carter Center. "This led to a lack of trust and social cohesion, which fuel trauma."

Trauma not only harms communities, but also hinders economic growth, according to the World Bank, which hopes a focus on mental health will kickstart Liberia's struggling economy.

It is working with the Carter Center on a $3 million project to train health staff in psychosocial treatment, set up support groups, lead community reconciliation efforts and tackle stigma.

"Trauma can affect economic output if children struggle at school, people become less productive at work or withdraw from society," said World Bank public health expert Carmen Carpio.

"Mental health issues cannot be seen in isolation."

MYTHS AND MISCONCEPTIONS

At least 400,000 of Liberia's 4.3 million people have mental health problems, yet the issue is ignored and there is only one psychiatrist and mental hospital in the country, experts say.

"Mental health conditions are invisible compared to other illnesses," Carpio said. "Illness is something people feel they can see and touch... those with mental health problems receive very little support, and are reluctant to seek help."

People with mental illness are often attacked or abandoned over fears that their condition is contagious and linked to witchcraft or violence committed during the bloody civil war.

Liberia's 166 mental health clinicians - mainly state nurses who received six months training in psychosocial support - teach people, religious leaders and even police about mental illness, and help to reintegrate people ostracised by their communities.

Tackling myths and misconceptions about mental health is vital to reducing stigma and addressing trauma, clinicians say.

Bill Jallah, a pastor and bipolar disorder sufferer, recalled a relapse where he found himself standing half-naked in the middle of a road in the early morning, confused and alarmed.

"People said: 'he must have been violent during the war', before throwing stones and coming at me with sticks," he said.

"Many struggle to believe a mentally ill person can have a job and a wife - and be a fully functioning member of society."

The clinicians also face stigma - even from other health workers who call them "crazy people doctors" - and have to deal with huge caseloads and harrowing stories of abuse and neglect.

"I treated a woman with psychosis who gave birth alone after her family shunned her," said Esther Bunder. "She and her baby were then kicked out of the family home and left on the street."

ECONOMIC IMPACT

Mental health sits firmly at the bottom of the list of health priorities for most West African nations, experts say.

But the inclusion of a target to promote mental health in the Sustainable Development Goals (SDGs) adopted by the United Nations in November could galvanise West African nations to improve mental health funding and services, Cooper said.

Liberia, which only introduced a mental health policy in 2009 and has no mental health law, should have focused on dealing with trauma after its civil war, said World Health Organization (WHO) mental health specialist Florence Baingana.

"Liberia should have cleaned out its wounds after the war... Now it must address suffering from the war, Ebola, and poverty."

While Liberia lost $240 million in gross domestic product due to Ebola, and saw economic growth plummet to 0.7 percent in 2014 from an original forecast of 5.9 percent, the economy should gradually pick up this year, analysts say.

But Liberia and other West African nations should consider the economic impact of untreated psychological trauma and mental illness, said Richard Mollica, adviser for the World Bank.

Mental illness will cost the global economy $16 trillion in lost economic output by 2030, more than other non-communicable diseases such as cancer, cardiovascular diseases and diabetes, according to research from Harvard and the World Economic Forum.

"Job and education prospects lead to better mental health, which fosters increased productivity and output," Mollica said.

"It is a smart investment to address mental health issues and livelihood opportunities early on - to avoid costly, long-term consequences for individuals, communities and countries."

Back at Kpalla school in Liberia's Montserrado county, several pupils gather round Korfeh for a group discussion.

"During Ebola many of our loved ones died... we felt sad all the time," said 15-year-old Bendu, who dreams of being a nurse.

"But the teachers have helped us - now we laugh and joke again. We talk about Ebola, instead of ignoring it like before."