Acute Flaccid Paralysis (AFP) Surveillance
AFP surveillance is the gold standard for monitoring the global polio eradication effort. It is used to detect potential cases of poliomyelitis in children under 15 years of age.
1. Definition and Criteria
- Clinical Definition: Any child (<15 years) with an acute onset of weakness or paralysis, characterized by flaccidity (reduced muscle tone) in one or more limbs.
- Objective: To identify and investigate all cases of AFP to rule out Wild Poliovirus (WPV) or Vaccine-Derived Poliovirus (VDPV).
2. The Surveillance Protocol
| Action | Requirement/Rationale |
|---|---|
| Stool Collection | Two stool specimens collected 24–48 hours apart, ideally within 14 days of paralysis onset. |
| Cold Chain | Samples must be maintained at 2–8°C and shipped to a WHO-accredited lab. |
| Follow-up | Clinical follow-up at 60 days to check for residual paralysis. |
3. High-Yield Clinical Pearls
- Non-Polio AFP: Most cases of AFP reported globally are actually Guillain-Barré Syndrome (GBS), transverse myelitis, or traumatic neuritis.
- Surveillance Indicator: A non-polio AFP rate of ≥2 per 100,000 children under 15 years is the WHO benchmark for a sensitive surveillance system.
NEET PG Hint: Remember: The stool samples must be collected as early as possible within the 14-day window of onset, because viral shedding is highest during this period. For more high-yield public health topics and free medical questions, visit mymedschool.org.