Wild polio and vaccine derived polio in Nigeria

After more than two years without the detection of wild polio in Nigeria, the Government reported three laboratory confirmed wild poliovirus type one (WPV1) cases with onset between July and August 2016.

All three cases were detected from Borno State, in children between 2 and 5 years of age. Two of them developed acute flaccid paralysis (AFP) while one was asymptomatic, identified as a close contact of a child with AFP.

The detected viruses are closely linked to WPV1 last detected in Borno in 2011. This is an indication that this virus strain has been circulating without detection since that time.