Fear of disease persisted in the Indonesian capital of Jakarta on Friday as parts of the city remained under muddy water and garbage piled up in poorer areas a week after devastating floods.

Flood waters have begun to recede, but 40 per cent of the area flooded last week in the low-lying city of 12 million people was still submerged on Friday, according to Indonesian Health Ministry officials.

Residents walk through mud in a neighbourhood hit by the flood in Jakarta, Indonesia, on Friday.
(Dita Alangkara/Associated Press)

Officials said the flooding killed 53 people and more than 240,000 people are still displaced from their homes.

Authorities say they have treated about 84,000 people for such ailments as itchy skin, coughs or common colds that may have been caused by unsanitary conditions or contact with dirty water.

The UN Health Organization, which has set up 15 mobile health units across Jakarta, is monitoring cases of acute respiratory tract infection, diarrhea, and leptospirosis, a bacterial illness that causes fever, severe headache and vomiting. It is said to be spread by rat urine.

Heavy rains overnight Thursday led to more flooding in the capital.

"We are concentrating on health issues to prevent diarrhea, cholera and leptospirosis outbreaks by clearing up places and water sanitation," Indonesian Health Ministry official Rustam Pakaya was quoted as saying by Reuters.

Several UN agencies have been providing assistance to Jakarta residents displaced by the flooding.

The UN World Food Program is delivering noodles and biscuits to one of the hardest-hit areas, while the UN Children's Fund is preparing water purification tablets and will provide zinc supplements to children to treat diarrhea.

"Hopefully the crisis has peaked, but we remain vigilant for potential floods as heavy rains continue to be predicted by the national weather services," UN humanitarian co-ordinator Bo Asplund said in a news release on Thursday.

Asplund said, if necessary, a UN Disaster Assessment and Co-ordination Team can be sent to the country if the situation worsens.

Mothers urged to breastfeed babies

UNICEF is also urging mothers to breastfeed their babies because infant formula mixed using dirty water could be deadly.

"We are concerned the lack of safe water could lead to an outbreak of diseases among children," UNICEF representative in Indonesia Gianfranco Rotigliano said in a statement, according to Reuters.

The Indonesian government, meanwhile, is providing emergency relief supplies and services, including food, drinking water, tents, sanitation facilities, and public kitchens.

The Indonesian army has set up a tent city in the middle of Jakarta to provide temporary housing.

On Friday, more than 500 people were reported to be staying in the tent city. Army officials said the site could be a temporary home for up to 1,000 people.

Indonesian authorities said they may spray disinfectant on Saturday in areas hard hit by the flooding, which occurred after rivers swollen by four days of torrential rain broke through barriers and inundated the city.

The forecast calls for more rain in the capital in the next few days and rainy season does not end until the end of March.

With files from the Associated Press