An outbreak of polio has been confirmed in Papua New Guinea, 18 years after the country was declared free of the disease.A public health emergency has been declared, media reported.

At least three provinces --Morobe, Madang and the Eastern Highlands -- confirmed the outbreak of the potentially deadly virus over this week following a meeting by the National Executive Council, Xinhua news agency reported. The public health emergency order will remain in place for at least 12 months, Minister for Health Puka Temu said.

The World Health Organisation (WHO) says the virus was detected in a six-year-old boy in April. The same strain of the virus has now been detected in other healthy children in the same community, making it officially an outbreak, the BBC reported. Polio has no cure and can lead to irreversible paralysis. It mainly affects children under the age of five, and can only be prevented by giving a child multiple vaccine doses.