The Indonesian branch of Caritas Internationalis, the global confederation of 162 Catholic relief, development and social service organisations, has warned that serious illnesses are starting to take hold among the victims of the Jakarta floods.

KARINA, Indonesia's branch of Caritas, has been busy ferrying relief supplies and evacuating people from their homes in Jakarta and other surrounding areas that are still submerged under flood waters.

But a new fight is emerging, to contain the further outbreak of diseases to unmanageable levels.

"Many people are getting sick, especially the children, who are not strong enough to be living in the temporary shelters," said Yohanes Baskoro, a volunteer who has been helping KARINA in the Jakarta area.

"We have been visiting some of the worst areas, such as along the Ciliwung River, and we've seen lots of problems with skin irritations and diarrhea. Many people are also suffering from dengue fever and respiratory illnesses," Mr Baskoro said.

The areas along the Ciliwung River are also some of the poorest areas of Jakarta, and there wooden homes were entirely swept away. People won't even have a home to return to, warns Caritas.

As an immediate response to the floods, KARINA launched an appeal through the Caritas network for just over $500,000 to care for victims of the flooding that began on February 1.

During the one-month emergency phase, the funds have already helped to procure KARINA a fleet of 40 rubber dinghies that it is now distributing among local partner organisations, and volunteers from the different dioceses and parishes have already been active over the past few weeks.

KARINA is also working through Indonesia's largest Muslim organisation in Indonesia, Nahdlatul Ulama, to reach out beyond the network of Catholic faithful to faiths of all kinds.

The humanitarian group, through its local partners, has also been distributing food and water, hygiene items, blankets, mosquito nets and sleeping mats to people in temporary shelters as well as those people who have decided to stay in or return their homes. Supplies will be distributed to 100,000 people.

Father Ignatius Ismartono, head of the Crisis and Reconciliation Service of the Indonesian Bishops' Conference, said, "We are now preparing the kits full of medicines to be given to medical teams, which we think is now the most important thing.

"The biggest danger is that as I look out my window now, there are dark clouds hanging, but in Jakarta it is not raining. But it might start raining in the hillsides, and all of the 13 rivers around the city pour into Jakarta. So we could be faced with a sudden rush of water unexpectedly," Father Ismartono explained.

Meanwhile, since the rains appear to have let up, many Jakartans have tried to return to their homes to salvage what they can.

Father Ismartono said that KARINA was keeping in close communication with other parishes and areas around Jakarta so that they could monitor the rains around the city. They are also closely following the weather reports, he said.

The rainy season is not expected to end for several more weeks, with its peak expected at the end of February.

The Indonesian government estimates that some 16,000 people remain displaced by the flooding, while some 80 people have died. At the peak of the floods, official figures placed the number of displaced at nearly half a million.