Acute anterior poliomyelitis (Polio virus)

Clinical criteria
Any person <15 years of age with acute flaccid paralysis (AFP)
OR
Any person in whom polio is suspected by a physician

Laboratory criteria
At least one of the following three:

Isolation of a polio virus and intratypic differentiation– Wild polio virus (WPV)
Vaccine derived poliovirus (VDPV) (for the VDPV at least 85% similarity with vaccine virus in the nucleotide sequences in the VP1 section)
Sabin-like poliovirus: intratypic differentiation performed by a WHO-accredited polio laboratory (for the VDPV a >1% up to 15% VP1 sequence difference compared with vaccine virus of the same serotype)

Epidemiological criteria
At least one of the following two epidemiological links:

Human to human transmission
A history of travel to a polio-endemic area or an area with suspected or confirmed circulation of poliovirus

Case classification
A. Possible case
Any person meeting the clinical criteria (in the absence of any alternative diagnosis)

B. Probable case
Any person meeting the clinical criteria and with an epidemiological link

C. Confirmed case
Any person meeting the clinical and the laboratory criteria

Current as of: 24 January 2019