A sharp spike in cases of paediatric acute flaccid myelitis is raising red flags with health officials who haven't identified a cause.AFM is now affecting young children in 22 different US states following a recent spike in Minnesota.Symptoms of AFM are similar to polio, whereby the disease affects the body's nervous system and can cause paralysis. Unlike polio, there is no vaccine for AFM.Sun Subscribers get the latest breaking news and videos directly to their feed. SUBSCRIBE NOW and hit the bell to be the first in the know.http://www.thesun.co.uk