Christian Aid has launched an appeal to help hundreds of thousands of people who urgently need food, shelter, clothing and medical help following the cyclone in Bangladesh.

An initial two week emergency response programme is already underway which will be followed by more long term recovery efforts.

Thousands will need help rebuilding their homes, decontaminating water supplies, replanting crops, and replacing livestock. The charity also warned that a lack of food would be a major problem in coming months as crops, which farmers were due to harvest next month, have been destroyed. In some areas the earlier summer crops were destroyed by severe flooding during the monsoon.

Christian Aid has already sent £100,000 to five partner organisations who are providing emergency food, cash and medical relief to 100,000 people in some of the worst hit areas and will be releasing more funds in the coming days.

Despite the ferocity of the cyclone, many lives were saved because early warning systems were in place and a million people were successfully evacuated to specially-built shelters. Many of these concrete shelters were build by Christian Aid after the super cyclone in 1991, which killed around 140,000 people.

"However, damage to homes, schools, livestock and crops has been extremely severe," said Neeti Bhargava, Christian Aid emergency programme officer, who has been travelling to affected villages by motorbike because roads are impassable by car.

Shrimp farms have been washed out and saltwater has contaminated freshwater supplies. Wells, roads and bridges are damaged and electricity supplies are affected. Over 50,000 people were injured by flying debris and falling trees and hundreds of thousands of livestock also perished.

Tota Mia, a farmer in Mozampurkandi village, lost his rice crop in the August flood. "Now I have lost my pulse crop too and my house was completely destroyed by the cyclone," he said. "We are sleeping under the collapsed house with the animals we saved."

Partner organisations are helping with rescue operations and evacuation. Gonoshasthaya Kendra, a local partner, is sending medical teams to treat up to 50,000 people who have sustained injuries in the severely affected areas of Pirojpur and Barguna.

On four islands in Potuakhali district off the coast of Bangladesh, another partner organisation, GUP, is the only relief agency providing relief to the very badly hit communities.

In the long term, efforts to help communities reduce their vulnerability to disaster need to be scaled up, Christian Aid said, adding that more cyclone shelters and megaphones were needed for early warning and protection in case of future disasters.