India declared cholera elimination from endemic transmission as a target for 2030 under the Global Roadmap to End Cholera. Regarding the oral cholera vaccine (OCV) used in India's outbreak response, which statement is CORRECT?
- A The WHO-prequalified Shanchol vaccine contains live attenuated Vibrio cholerae O1 and O139
- B OCV alone is sufficient for cholera control without concurrent WASH interventions
- C Shanchol (whole-cell, killed bivalent OCV) provides about 65% efficacy in the first year and can be used as a single dose in reactive vaccination ✓
- D OCV provides lifelong immunity after two doses, making re-vaccination unnecessary
Explanation
Shanchol is a WHO-prequalified, killed whole-cell bivalent oral cholera vaccine covering V. cholerae O1 (El Tor Inaba and Ogawa biotypes) and O139. It is NOT a live vaccine. Standard schedule is two doses, but since 2018 WHO endorses single-dose reactive vaccination campaigns in outbreak settings when two-dose logistics are challenging, providing moderate short-term protection. Efficacy is approximately 65% in the first year and declines over time. OCV is complementary to — not a replacement for — WASH (water, sanitation, hygiene) interventions. Two-dose efficacy protection lasts 2–3 years, necessitating revaccination in endemic settings.
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.