At least 28,000 people are still affected by flooding in the Budalangi area, in Kenya's western district of Busia, a humanitarian official has said.

"An estimated 6,000 to 8,000 internally displaced people are in six camps while a further 2,000 remain marooned," Mercy Manyala, a national officer with the UN Office for the Coordination of Humanitarian Affairs (OCHA), Kenya office, said on 27 September.

Budalangi has an estimated population of 64,000 and experienced the latest deluge with the collapse of a dyke on the River Nzoia in August.

"It is difficult to get information on who is displaced," Manyala said.

There are also no exact figures available on the number of people affected in terms of age, yet this is important for planning purposes as children and other vulnerable groups need special care, she said.

According to Manyala, there were no particular health problems among the displaced although there had been increases in malaria cases after the initial rains in August but this had normalised.

However, she said, there was a need for the provision of adequate clean water in the camps. At least 260 families are camped at the Mukhobola health clinic with only one water tank, she said.

Moreover, she said, additional portable toilets were needed as the ones in the camps were filling up quickly.

The families at Mukhobola are using the health centre's toilets, which have now filled up, and the public health officials are considering closing them down, she said.

"The tarpaulins being used for shelter in the camps are also not enough and this might expose the people to the threat of pneumonia," she said.

The flooding has affected two health centres and submerged some schools, forcing the students to move to makeshift classes in the schools on higher ground.

Meanwhile, food distribution for the affected families is ongoing, with an aerial distribution of 7.5 metric tonnes for the marooned families on 25 September in the Bongo and Musoma areas, Manyala said.

So far, the Sidukhumi, Musoma, Rukala, Buluuani, Bubamba, and Bongo areas remain flooded, she said.