The World Health Organization reported on Monday that a case of vaccine derived polio has paralyzed a child in Bamako, the capital of Mali. The WHO is organizing an emergency vaccination drive to halt any further outbreak.
The Guinean child whose parents traveled to Bamako seeking medical care, is carrying a virus closely matched to a strain last detected in Guinea in 2014.
This case is caused by a strain of the virus known as type 2 and is the third reported case of its kind in a week. Two cases were reported last week in eastern Ukraine.
There were fifty five cases of vaccine derived polio paralysis in the world in 2014 and thirteen this year.
Outbreaks of the vaccine derived virus are contained by doing several successive rounds of vaccination in areas where cases are first reported. In areas where vaccination coverage is minimal the risk of the disease spreading is high.