A cluster of 12 cases of acute watery diarrhoea occurs in a village within 24–48 hours of a community feast. Vibrio cholerae O1 Ogawa biotype El Tor is confirmed. The R₀ for cholera under these conditions is most likely in the range:
- A < 1, indicating the outbreak will self-limit without intervention
- B 1–2, indicating limited transmission potential
- C 2–5, indicating moderate epidemic potential requiring containment ✓
- D > 10, comparable to measles in unvaccinated populations
Correct answer: C. 2–5, indicating moderate epidemic potential requiring containment
Explanation
The basic reproductive number (R₀) for cholera in epidemic conditions has been estimated at approximately 2–5, reflecting moderate but significant epidemic potential dependent on sanitation, water contamination, and population immunity. The El Tor biotype, particularly the O139 serogroup, has displaced the classical biotype globally due to environmental persistence. An R₀ > 1 confirms epidemic potential; without WASH interventions and case isolation, secondary transmission through contaminated water will sustain the outbreak.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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