Question

On the basis of serological specificity of Clostridium botulinum toxins, which of the following types do not cause disease to humans?

• A. A and B
• B. C and D
• C. E and F
• D. A and G

Hint:

Type E botulism is highly associated with marine and freshwater environments.
Consequently, it is the primary type of botulism toxin found in outbreaks linked to under-processed canned fish and vacuum-packed seafood products.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Clostridium botulinum synthesizes powerful, antigenically distinct neurotoxins.
Based on the serological specificity of these toxins, the species is divided into seven major toxicological types designated A through G.

Step 2: Detailed Explanation:
The seven toxin types exhibit host-specific pathogenicity:
- Types A, B, E, and F: These are the primary causative agents of foodborne, infant, and wound botulism in humans.
- Types C and D: These toxins are highly pathogenic to non-human mammals and birds (causing botulism in poultry, wild birds, cattle, and horses). They do not cause disease in humans under natural conditions.
- Type G: Highly restricted and rarely associated with human disease.

Step 3: Final Answer:
The toxin types that do not cause disease in humans are types C and D, which corresponds to option (B).