What is the wrong statement about passive acquired immunity?

Options

A. Host immune system does not participate
B. Induced by antigen
C. Applicable in immune deficient host
D. Used for treatment in acute infection.

Answer

### Step-by-Step Solution

1. **Understanding Passive Acquired Immunity**:
- Passive acquired immunity involves the introduction of preformed antibodies into the body. This means that the immune system does not actively produce these antibodies; instead, they are provided from an external source.

2. **Types of Passive Immunity**:
- There are two main types of passive immunity:
- **Natural Passive Immunity**: This occurs when antibodies are transferred naturally, such as from mother to fetus through the placenta (IgG) or through breast milk (IgA in colostrum).
- **Artificial Passive Immunity**: This occurs when preformed antibodies are administered to an individual, typically in response to an emergency situation involving a pathogen.

3. **Analyzing the Statements**:
- The question asks which statement about passive acquired immunity is incorrect. We need to evaluate each option provided:
- **Option A**: "Host immune system does not participate."
- This statement is **correct** because the host does not produce the antibodies; they are given directly.
- **Option B**: "Induced by antigen."
- This statement is **incorrect**. Passive immunity does not involve the host's immune system inducing antibodies through exposure to an antigen. Instead, it involves the direct administration of antibodies.
- **Option C**: "Applicable in immune deficient host."
- This statement is **correct** because passive immunity can be particularly beneficial for individuals whose immune systems are compromised.
- **Option D**: "Used for treatment in Acute Infection."
- This statement is also **correct** as passive immunity is often used to provide immediate protection during acute infections when the body cannot produce antibodies quickly enough.

4. **Conclusion**:
- The incorrect statement about passive acquired immunity is **Option B**: "Induced by antigen."