**Question:** The chance that a health worker gets HIV from an accidental needle prick is-

A. 90%
B. 30%
C. 10%
D. 5%

**Core Concept:** HIV (Human Immunodeficiency Virus) is a virus that attacks CD4+ T cells, leading to acquired immunodeficiency syndrome (AIDS). Health workers are at risk of acquiring HIV through specific modes of transmission, including needle stick injuries.

**Correct Answer: D. 5%**

**Why the Correct Answer is Right:** The correct answer is 5%, which represents the percentage of health workers who contract HIV after an accidental needle stick. This value is derived from various studies conducted on the risk of HIV transmission in such cases.

**Why Each Wrong Option is Incorrect:**

**A. 90%:** This option is incorrect because it significantly overestimates the actual risk. Studies show that HIV transmission after a needle stick injury is much lower than 90%.

**B. 30%:** Similarly, this option is incorrect due to the substantial underestimation of the actual risk. The actual risk is lower than 30%.

**C. 10%:** The correct answer is 5%, making 10% an incorrect estimate.

**Clinical Pearl:** The risk of HIV transmission after an accidental needle stick injury can be significantly reduced by proper infection control measures, such as using needles and syringes for a single patient, employing sterilization and disposal techniques correctly, and administering post-exposure prophylaxis (PEP) if available and administered within 72 hours of exposure.

**Core Concept (Reinforced):** HIV transmission can occur via specific routes, including bloodborne pathogens like hepatitis B and C, and in some cases, HIV. Health workers must adhere to strict infection control measures to minimize the risk.

**Why Each Wrong Option is Incorrect:**

**A. 90%:** This option is incorrect because it greatly overestimates the actual risk, which is much lower than 90%.

**B. 30%:** As mentioned above, this option is incorrect due to the substantial underestimation of the actual risk, which is lower than 30%.

**C. 10%:** The correct answer is 5%, making 10% an incorrect estimate.

**Clinical Pearl:** Proper infection control measures and prompt administration of PEP can significantly reduce the risk of HIV transmission after an accidental needle stick injury. It is crucial for healthcare workers to follow these guidelines to minimize the risk of exposure to bloodborne pathogens.