Which of the following is not a first generation vaccines?

Options

A. BCG
B. OPV
C. Cholera vaccine
D. Hepatitis B vaccine

Answer

To determine which of the following vaccines is not a first-generation vaccine, we need to understand what first-generation vaccines are. First-generation vaccines are typically made from live attenuated pathogens, which are weakened forms of the pathogen that can still elicit an immune response without causing the disease.

Let's analyze the options provided:

1. **BCG (Bacillus Calmette-Guérin) Vaccine**:
- This vaccine is used to prevent tuberculosis and is made from a live attenuated strain of Mycobacterium bovis.
- Since it is a live attenuated vaccine, it is classified as a first-generation vaccine.

2. **OPV (Oral Polio Vaccine)**:
- This vaccine is used to prevent poliomyelitis and is also made from live attenuated poliovirus.
- Therefore, OPV is also a first-generation vaccine.

3. **Cholera Vaccine**:
- The cholera vaccine is typically made from killed or inactivated bacteria, which means it does not use live attenuated pathogens.
- However, there are live attenuated cholera vaccines as well, but the commonly used ones are not classified as first-generation vaccines.

4. **Hepatitis B Vaccine**:
- This vaccine is made using recombinant DNA technology and contains only a part of the virus (the surface antigen), not the live virus itself.
- Therefore, it is not a first-generation vaccine.

Based on this analysis, the vaccine that is not a first-generation vaccine is the **Hepatitis B vaccine**.

### Final Answer:
The vaccine that is not a first-generation vaccine is the **Hepatitis B vaccine**.