Vibrio cholerae O139 Bengal differs from O1 El Tor in that it:
- A Does not produce cholera toxin
- B Possesses a capsule providing serum resistance and is not agglutinated by O1 antiserum ✓
- C Is more common in freshwater environments
- D Is susceptible to standard O1 vaccines
Correct answer: B. Possesses a capsule providing serum resistance and is not agglutinated by O1 antiserum
Explanation
V. cholerae O139 Bengal emerged in 1992 in India and Bangladesh as the only non-O1 serogroup to cause epidemic cholera. Its key distinguishing feature is the presence of a polysaccharide capsule (encoded by a genomic island absent in O1) conferring serum resistance and preventing agglutination by O1 antiserum. Existing O1 vaccines do not protect against O139 because of the different O-antigen.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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