Deadly cholera is spreading through drought-ravaged Somalia as clean water sources dry up, a top aid official said, deepening a humanitarian crisis in a country that is on the verge of famine.

The Horn of Africa nation has recorded more than 18,000 cases of cholera so far in 2017, up from around 15,000 in all of 2016 and 5,000 in a normal year, Johan Heffinck, the Somalia head of EU Humanitarian Aid, said in an email on Thursday.

The current strain of the disease is unusually deadly, killing around 1 in 45 patients.

Somalia is suffering from a severe drought that means more than half of its 12 million citizens are expected to need aid by July.

Families have been forced to drink slimy, infected water after the rains failed and wells and rivers dried up.

“We are very close to famine,” Heffinck said. The Security Information Network (FSIN), which is co-sponsored by the United Nations food agency, said in a report on Friday Somalia was one of four African countries at high risk of famine.

Somalia’s rainy season normally runs from March to May, but there has been no rain this month.

The drought has hit particularly hard in the breakaway northern region of Somaliland, where the rains began to fail in2015, killing off animals that nomadic families rely on to survive.

– By REUTERS