Components of AFP Surveillance

The objective of AFP surveillance is to detect the exact geographic locations where wild polioviruses are circulating in the human population. All cases of acute flaccid paralysis in children aged <15 years are rigorously investigated by a trained medical officer, with collection of stool specimens to determine if poliovirus is the cause of the paralysis. Analysis of the location of polioviruses isolated from AFP cases allows programme managers to plan immunization campaigns (Pulse Polio Immunization) to prevent continuing circulation of virus in these areas.

Case Definition:

In the Global Polio Eradication Initiative (PEI), acute flaccid paralysis is defined as:

Any case of AFP in a child aged <15 years, or any case of paralytic illness in a person of any age when polio is suspected.

Acute: rapid progression of paralysis from onset to maximum paralysis
Flaccid: loss of muscle tone, “floppy” – as opposed to spastic or rigid
Paralysis: weakness, loss of voluntary movement

Any case meeting this definition undergoes a thorough investigation to determine if the paralysis is caused by polio.

Components of AFP Surveillance