Nazha Mohammed was pale and silent in her mother’s arms, on the edge of listlessness. At 2 months old, she was one of the youngest children inside a high school where several hundred Yemenis have sought refuge from conflict.

“There’s no milk for her,” explained her father, Mohammed Yahya.

Yemen’s populist uprising and the political crisis that followed have pushed the country to the brink of a humanitarian emergency, according to the United Nations and aid agencies. And children have been hit especially hard.

Malnutrition rates are rising. Children are, more than ever, vulnerable to life-threatening illnesses and diseases. They are being deployed as soldiers by all warring sides, and scores have been killed in the crossfire. Many schools have been shut down.

“It’s absolutely valid to say children are bearing the biggest brunt of the political situation here,” said Geert Cappelaere, UNICEF director in Yemen.

Of all the countries in the Arab world altered by populist revolts last year, Yemen was by far the poorest and least developed. The country has long faced multiple crises, from a civil conflict in the north to a secessionist movement and strife in the south. That has prevented aid agencies from adequately providing assistance to many areas and plunged ordinary Yemenis into a downward spiral.

Their situation has worsened over the past year, according to aid workers. The embattled government of President Ali Abdullah Saleh, which for years lacked authority over much of the country, was preoccupied with remaining in power. Fresh conflicts, including a raging battle between the government and Islamist militants, have disrupted basic services; water, fuel and electricity shortages affect nearly every aspect of life, from hospital operations to trash collection. Food prices are rising, and health services have collapsed.

In a nation in which half the population is younger than 18, many aid workers fear that the political crisis and the problems it has spawned will be felt beyond this generation of children.

“Development gains have been erased. In some areas, they have gone back five to 10 years,” Cappelaere said. “Today, we’re like a fire brigade, extinguishing one fire but never sure it will not start again tomorrow. And while we are responding to one fire, there are three other fires starting elsewhere.”

Hampered by trauma

Girls, especially from rural areas, face conditions that are even more dire. With rising poverty and increased displacement from the violence, many now have to take on more responsibilities, in a nation that already has the lowest school enrollment rate for girls in the Middle East. Aid workers worry about an increase in families marrying off young daughters to ease financial pressures.

Many children also grapple with symptoms of social and psychological traumas, such as constant nightmares, that could hamper their development, aid workers and psychologists say. “Every time they hear a plane, they get scared and run away,” Safaa Ali, a UNICEF-funded worker who works with psychologically traumatized children, said in a report published on UNICEF’s Web site.

Meanwhile, with Yemen fragmented into numerous centers of power, aid agencies are forced to get the approval of as many as 20 or 30 tribal leaders before they can provide services to a single area.

In the north, one of the most devastated parts of the country, Shiite Houthi rebels control three governorates and have long been suspicious of Westerners. Cappelaere recounted an incident last year in which Houthi leaders refused to allow children to be immunized because the vaccines were made in the United States.

“You may be poisoning our children,” a Houthi official told him. So UNICEF had to fly in vaccines made in India, Cappelaere said.

Encamped in classrooms

Tens of thousands of Yemenis have come to Aden after being displaced by fighting in nearby Abyan province, where government forces are battling militants linked to al-Qaeda who have taken over large swaths of the province. The refugees are encamped in about 60 schools in this southern port city. For tens of thousands of children here, that has meant the loss of an entire school year — as it has for children in the capital, Sanaa, and other cities roiled by political unrest.

In Lutfi High School, 76 families, including 150 children, reside in classrooms, as many as three families to a room. Boys, some as young as 8, are often made to wash cars or sell snacks on the streets to help provide for their families.

“My children can’t sleep,” said Yahya, 31, father of the 2-month-old who needs milk. He fled with his four children from the city of Zinjibar, 35 miles to the north, last year. “I don’t know what will happen to them.”

Salah Nasser Nashir, 34, fled Zinjibar in July. Last month, his pregnant wife started bleeding. When he took her to a hospital, he was told that there was a shortage of blood and that he would have to pay for a supply — or find donors quickly.

So he sold some rations given to him by a local aid agency and rushed back to the hospital to save his wife.

“The baby died anyway,” he said.