First suspected police case in 21 months in India

Sources say that the 18-month-old child is under detailed investigation and the results will come only after a week's time. The boy child has reportedly been immunised for polio 13 times and authorities are investigating the reason for the infection, sources told PTI.

"The case is under detailed investigation. It will take about a week to get the results. As a measure of abundant precaution, an immunisation drive is being carried out in 28 districts of Bihar early next week," an official of the Health Ministry said.

The case is suspected to be of wild poliovirus type 3 (WPV3) and Bihar has not had any case of WPV3 since January 2010. The WPV3 polio strain is found in Nigeria and Pakistan.

Sources said that the child is reported to have nutrition deficiency and further investigations are on.

India has been polio free since January 13, 2011 when the last case polio was detected in West Bengal. The country recorded only one case of polio throughout 2011, when a child in Howrah, West Bengal, was paralyzed on 13 January and no case has been reported since then.

India was officially struck off the list of polio-endemic countries by the World Health Organization (WHO), having gone more than one year without reporting any cases of wild poliovirus.

As per WHO norms, India has to remain polio-free for three consecutive years before being declared polio free.

Only three countries in the world are now considered polio-endemic