The Sahel state is one of the African countries still afflicted by the spaghetti-like parasite worm, which can grow up to one metre (3 ft) long and pushes out of the host's skin through blistering, pus-filled wounds to deposit larvae.

The burning pain sends many victims into the nearest available water for relief and unless boiled or filtered the contaminated water is likely to infect those who drink it.

Niger's health ministry announced the reward of 5,000 CFA francs ($11.35) would also be given to sufferers of the parasite who identified themselves to officials within 24 hours of the disease appearing and who had not contaminated a water source.

In a message broadcast on state radio, the ministry urged the nearly 14 million inhabitants of the largely arid West African state to drink water from safe sources like wells and otherwise boil it before drinking.

Suspected Guinea worm sufferers should be reported to the authorities and prevented from entering bodies of water, the ministry added.

Niger is participating in a campaign to eliminate Guinea worm in the world by 2009 launched by the U.S. Carter Center, an aid group set up by former U.S. President Jimmy Carter.

Recorded cases of Guinea worm in Niger had fallen sharply to 14 in 2007 from 33,000 in 1991. Authorities said the latest cases had been reported in the western region of Tillabery, where the Niger river crosses the country.

Sudan is home to four-fifths of the world's cases of Guinea worm, also known as dracunculiasis. Other African countries afflicted are Ghana and Niger's neighbours Mali and Nigeria.

When the Carter Center started tackling the disease in 1986, there were 3.5 million cases worldwide. In 2006, only 25,217 cases were recorded and just over 20,000 of those were in Sudan.