• Women, children most vulnerable in Pakistan crisis

Pakistan's displaced flood victims say a lack of clean water and high temperatures are causing illnesses sweeping through relief camps with children most at risk.

Almost five million people are currently without shelter following devastating flooding sparked more than a month ago by heavy monsoon rains.

"They are scared, traumatized," said Bibi Luqmania, 30, whose four children live with her in a tent donated by the charity Islamic Relief. "And it's so hot in the tent, they cannot stand it. It becomes like an oven during the day."

Luqmania is one of 400,000 people displaced by the flooding in the Khyber-Pukhtunkwa district of Nowshera, and now lives in the Khandar 1 camp established at the Khandar Technical College.

Seventeen million Pakistanis have been affected and the United Nations says only 64 percent of the funds required to meet the $458 million cost of the crisis have been found.

Luqmania worries her two eldest children will not be able to continue school, and that her youngest, a three-year-old girl swarmed by flies, will fall ill.

Her comments are echoed by Asahet, 50, who sits on a rope bed surrounded by young children and family members.

"There are two main problems facing the children here. They are traumatized - they have lost their homes, everything.

"And it's far too hot in the tents here, and we have no fans," she said.

Lack of basic hygiene causes illness.

"We used to bathe once or twice a day at home," she said. "Here we only have water to wash every four days. We are getting skin infections and some people have eye infections."

Twenty minutes away in the Pabi Satellite Hospital, doctors at the Diarrhea Treatment Center have been inundated.

Dr Asad Ullah works at the center, where 1,180 people have been seen by doctors since the center opened on August 21, and says women and children make up the bulk of patients.

"Mothers and children are particularly at risk from catching and spreading illnesses because they have the closest contact with other children," said Ullah.

The center is run jointly by the World Health Organization, and British charity Merlin. Running a spotless ward, the charities are maintaining medical supplies, and doctors say the Pakistani government is ensuring ceiling fans are working to cool patients.

WHO representative Dr Sulaiman Durrani said 70 percent of those being treated were children under five. Severe dehydration, skin and eye infections and malnutrition have also been reported.

Ullah expressed fears of trauma.

"We are seeing traumatized children who are in shock coming in - if it is difficult to take a pulse reading, attach a drip, or get the patient to explain what is wrong, we say they are in shock. "We worry we could see psycho-social problems among people traumatized by their experiences."