Cholera cases have soared in the Democratic Republic of Congo in recent weeks, the UN said on Friday, bringing the number of people infected in the year-long outbreak to 22,000 with 584 deaths.

Aid agencies have been trying to halt the spread of the water-borne disease that has ravaged eight of the country's 11 provinces since January 2011.

"There has been a spike in cases" since mid-December, with figures on the rise in the capital Kinshasa in particular, the UN Office for the Coordination of Humanitarian Affairs (OCHA) said.

Cholera, a contagious intestinal infection, has taken its heaviest toll on eastern regions however, with a quarter of all cases reported in Sud-Kivu province.

The UN Central Emergency Response Fund has allotted $4.4 million to children's aid agency UNICEF and $4.7 million to the World Health Organisation to help combat its spread.

"Aid organisations say they are confident that they will beat this emergency, but added that durable solutions are required and that the Congolese authorities will need to prioritise investments in clean water, sanitation and hygiene," OCHA said in a statement.