A 22-year-old Pakistani student in Australia has tested positive for polio, a World Health Organization official says
The case is the first in Australia since 1986, officials say.
Zaheer Ahmed from Punjab apparently contacted the virus on a recent visit to Pakistan, officials say.
Pakistan is one of only five countries in the world where the polio virus still exists. Eleven new cases have been reported so far this year.
In northern Pakistan, hardline clerics are conducting a campaign against polio vaccination, saying it is a US conspiracy to render people incapable of producing children.
Mr Ahmad, a student living in Melbourne, came to Pakistan in March and visited its northern tourist resorts of Swat and Kalam, Dr Sarfraz Khan Afridi, a surveillance officer of the WHO told the BBC.
He returned to Melbourne on 30 June, and soon afterwards developed problems in his legs which were diagnosed as polio, he said.
He said the student had been quarantined.
Dr Khalife Mahmud Bille, the WHO's country chief in Pakistan, told the BBC that the Australian government had expressed concern over the detection of a polio case on its soil and had sent information about it to the Pakistani authorities.
According to Dr Bille, a sample of the virus received from Australia was tested for genetic sequencing and was found to closely resemble a polio case detected in Pakistan's Khyber tribal agency in October 2006.
The WHO surveillance staff found that during his visit to northern Pakistan, Zaheer Ahmed stayed at a hotel owned by a resident of Khyber Agency.
Northern Pakistan has been the scene of a campaign by hardline clerics who have been telling people that the polio vaccine is designed to render their children sexually impotent.
They say it is a conspiracy of the Western powers to restrict the Muslim birth rate.
The WHO's polio vaccination teams have repeatedly failed to achieve vaccination targets in large parts of northern Pakistan over the past year.
The region accounts for more than half the polio cases reported in the country each year.
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