For adequate acute flaccid paralysis (AFP) surveillance, what is the correct standard for stool specimen collection from an AFP case?

• A One stool sample collected within 7 days of onset of paralysis
• B Two stool samples collected within 28 days of onset, at least 48 hours apart
• C Three stool samples collected on alternate days starting at onset
• D Two stool samples collected within 14 days of onset, at least 24 hours apart ✓

Explanation

AFP surveillance quality is judged by whether two adequate stool specimens were collected within 14 days of onset of paralysis, separated by at least 24 hours, each of sufficient quantity (about 8 grams), and transported cold with proper documentation. Virus excretion is highest and most reliably detectable in this window. A single specimen misses intermittent viral shedding, and delays beyond 14 days sharply reduce isolation rates, so these parameters define the surveillance indicator.

Reference: WHO Manual for the Virological Investigation of Polio, WHO/EPI/GEN ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.