The United Nations says at least 44 people have died in a cholera outbreak in the militancy-hit northeast of Nigeria, where the first case of the disease was identified nearly five weeks ago.

The world body said in a statement that nearly 2,300 confirmed or suspected cases of cholera had been registered by Monday.

"To date, the outbreak has claimed at least 44 lives, out of close to 2,300 confirmed and/or suspected cases," read the statement.

The United Nations Office for the Coordination of Humanitarian Affairs (OCHA) has said that nearly $10 million is needed to keep the disease from spreading.

Additional funding would assist to implement a cholera response and prevention plan in the coming months, including providing access to clean water and a vaccination program.

Peter Lundberg, OCHA's deputy humanitarian coordinator for Nigeria, said that despite new treatment centers and sanitation measures, more needed to be done.

"The camps for displaced persons are congested, there is not enough water, sanitation facilities are poor, and the health care system is weak," Lundberg said, adding, "We must tackle this urgently to avoid preventable suffering and loss of life."

The first cholera case was identified in Borno State on August 16 and has since spread, mainly in camps for those displaced by the Boko Haram Takfiri terrorist group.

Cholera is an acute diarrheal infection spread by contaminated food and water. It can be easily treated with oral rehydration solution if caught early, but the disease can kill within hours if left untreated.

The latest figures by the UN suggest a 4.3 percent fatality rate -- well above the 1 percent rate that the World Health Organization rates as an emergency.

Cholera is just one of the challenges facing the Nigerian government, which is still struggling to expand its authority in the militancy-wracked northeastern states.

Last week, Mark Lowcock, the UN head of humanitarian affairs and emergency relief, said that the threat of famine caused by the conflict's impact on farming had been averted.

But 8.5 million people in the northeast, out of 17 million in the wider Lake Chad region comprising Nigeria, Cameroon, Chad and Niger, needed humanitarian assistance, Lowcock added.

Northeast Nigeria is already in the grip of a humanitarian crisis caused by the Boko Haram insurgency, which has killed at least 20,000 people and displaced more than 2.6 million since 2009.