A 2-year-old child with acute flaccid paralysis is reported to the district surveillance officer. For the case to meet the criterion of 'adequate' stool specimen collection for poliovirus isolation, stools must be collected:

• A Two samples at least 24 hours apart, within 14 days of onset of paralysis ✓
• B One sample within 48 hours of hospital admission
• C Two samples at least 24 hours apart, within 21 days of onset of paralysis
• D Three samples on consecutive days, within 7 days of onset of paralysis

Explanation

AFP surveillance defines adequate stools as two specimens collected at least 24 hours apart, both within 14 days of onset of paralysis, each of sufficient quantity (about 8 grams) and reaching the laboratory in good condition under reverse cold chain. The 14-day window exists because faecal excretion of wild poliovirus is highest early in illness, maximising culture sensitivity. Beyond 14 days, isolation rates fall sharply.

Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.