An estimated six million children are at risk of malnutrition, diarrhoea and pneumonia as unprecedented super-floods inundate Pakistan.

As flood waters rush south through Sindh and southern Punjab, DEC agencies are warning that as the polluted waters hits densely populated urban areas in the south, where poverty levels are even higher than in the north, the health risks to children are huge.

Mohammed Qazilbash, Save the Children’s spokesperson in Islamabad said: “Outbreaks of cholera and malaria are a big concern. In southern Punjab and Sindh there are vast numbers of people living right along the water, some in makeshift houses with very poor hygiene and sanitation at the best of times.

“Children are drinking, washing in and going to the toilet in the same river water. If this sanitation crisis is not tackled now, in six months time, millions and millions of children will be suffering potentially deadly diarrhoea and other diseases.

Southern Pakistan is much hotter and flatter than the mountainous regions in the centre and north of the country. Here, water will not run off quickly but stand for long periods of time before evaporating. In temperatures currently hovering over 30 degrees Celsius, these flood plains will fast become huge breeding grounds for mosquitoes and malaria.

Doctors working in flood-affected northern areas of Punjab and Swat Valley are already reporting an alarming increase in the number of patients suffering from water-borne diseases including diarrhoea, food poisoning, vomiting and fever. There are also reports of measles outbreaks among children in temporary camps for the millions displaced by the disaster.

Save the Children and World Vision medical teams working in Lower Dir, Allai and Swat Valley each treat between 600 and 700 patients every day for ailments ranging from respiratory and skin infections to trauma. Over 60% of patients are women and children.

Mark Bulpitt, Head of Emergencies for World Vision UK adds: "As we continue to reach those most affected by this flood, we must also focus on the longer-term recovery, prioritising livelihoods and education to ensure more of Pakistan's children do not become victims of child labour. Schools have been washed away so education will need to be prioritised, houses and health centres are unusable and then there is the emotional fallout of living through a disaster as devastating as this one."

The true scale of destruction of agricultural land, homes, sewage systems, schools and livelihood is not yet know, but the UN is appealing for £290m to help fund its efforts alongside the Pakistan government in coming months.

The DEC raises funds for its member agencies which have now distributed aid to more than 500,000 people affected by the flooding.