Pakistani officials say pneumonia is spreading among children who survived the October earthquake that left more than three million people out in the cold.

They say hundreds of homeless people have contracted pneumonia in the quake-zone as the harsh Himalayan winter sets in.

The Himalayan region got its first harsh winter weather at the weekend with up to 20 centimeters of snow falling at some high altitudes and heavy rain in some lower areas, bringing relief operations to a halt.

Aid agencies are racing to ensure that survivors get adequate shelter and enough food to see them through the winter.

Relief workers say the fear is that disease could sweep through cold, poorly nourished survivors, causing a second wave of deaths.