It said the region around the capital Khartoum had been particularly badly hit and was experiencing the worst floods in 25 years.
One of the major risks to health was the collapse of more than 53,000 latrines, the WHO added.
A UN official in Sudan described the situation as “a huge disaster”.
In a report, the WHO said that 48 people had been killed and 70 injured in the floods. It warned of increasing trends of malaria cases in the past two weeks.
Meanwhile, Sudan Interior Minister Mahmoud Hamed put the confirmed death toll at 53, according to the AFP news agency.
The WHO also said property had been damaged in 14 of Sudan’s 18 states.
Mark Cutts, the head of the UN Office for the Co-ordination of Humanitarian Affairs in Sudan, told AFP last week the world body was ready to help those affected by the disaster.
He added that this was despite the fact that UN humanitarian operations “have been severely underfunded” this year.
- In2EastAfrica
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