A cholera outbreak in Iraq is spreading, the World Health Organization said Tuesday, with new cases confirmed in Baghdad, Basra and, for the first time, three northern districts.

The number of confirmed cases has now reached 2,116, WHO said. Just a day earlier, a WHO official put the number of confirmed cases at 1,652. Eleven people have died of the disease so far.

"It shows that people are moving, and when people are moving they are spreading cholera," said Claire-Lise Chaignat, a cholera expert at WHO. The global health body estimates that more than 30,000 people have fallen ill with acute watery diarrhea, which may later be confirmed as cholera.

More than two-thirds of confirmed cases are in the northern province of Kirkuk, where cholera was first reported on Aug. 13, WHO said.

While the number of deaths from the disease has so far been low, "it continues to spread across Iraq and dissemination to as yet unaffected areas remains highly possible," WHO said.

A new case in Baghdad has taken the number of confirmed infections there to two, said WHO spokeswoman Fadela Chaib. On Monday, a woman in the Iraqi capital died from the disease.

Cholera is a gastrointestinal disease that is typically spread by drinking contaminated water and can cause severe diarrhea that in extreme cases can lead to fatal dehydration.

It can be prevented by treating drinking water with chlorine and improving hygiene conditions.