New York, May 3: A case of polio has been detected in Indonesia, World Health Organisation officials said yesterday, indicating that an outbreak spreading from northern Nigeria since 2003 has crossed an ocean and reached the world?s fourth most populous country.

The virus, found in a village on the island of Java, is most closely related to a strain that was found in Saudi Arabia in December, the officials said. The most likely explanations of how it got there are that it either was brought back by an Indonesian working in Saudi Arabia or by a pilgrim who went to Mecca in January.

Indonesia?s last case was in 1995, and it is now the 16th country to be reinfected by a strain of the virus that broke out in northern Nigeria when vaccinations stopped there, then crossed Africa and the Red Sea.

Officials recommended that Indonesia immediately vaccinate five million children on the western end of Java, including the capital, Jakarta, to contain the virus. The country began planning such a drive last week, they said.

Indonesia has more Muslims than any other nation, and polio is now found almost exclusively in Muslim countries or regions.

Resistance to polio vaccine has been high from northern Nigeria to the Pakistan frontier because of persistent rumours that it is a western plot to render Muslim girls infertile or to spread AIDS.

Paradoxically, after several states in Muslim northern Nigeria halted vaccinations in 2003, it was purchases of Indonesian vaccine that persuaded wary imams and politicians to drop their opposition, because it is a Muslim country. With each new case, the WHO?s goal of eradicating polio by the end of this year slips farther away.

With its emergency response fund virtually depleted, the organisation is pleading with donors for help with containing new outbreaks in Ethiopia, Yemen and other very poor countries.

At the disease?s low point, in early 2003, it was endemic in only six countries: Nigeria, Niger, Egypt, Pakistan, Afghanistan and India.

The current case was found in a village in Sukabumi Province in West Java in an 18-month-old boy who became paralysed in mid-March, said Dr Bruce Aylward, coordinator of the polio eradication drive for WHO.

Genetic typing of the virus, completed in India, shows that the original source of the strain was northern Nigeria, said Dr David L. Heymann, the WHO director general?s representative for polio eradication.

Comparison with databases at the Centers for Disease Control and Prevention in Atlanta shows that it is about 99.2 per cent similar to a strain circulating in Saudi Arabia and 99.1 per cent similar to a strain in Sudan, suggesting that it came through Saudi Arabia, ?but they?re so close that it?s a hard call,? Dr Aylward said.

Dr Christopher P. Maher, chief of technical support in WHO?s polio division, visited Sukabumi last week and found that no relatives of the child had gone to areas where polio was endemic, but other families in the village had members who had gone recently to Saudi Arabia as workers or pilgrims.