The chance that a health worker gets HIV from an accidental needle prick is –

**Core Concept**
The risk of acquiring HIV from an accidental needle prick, also known as needlestick injury, is a significant concern among healthcare workers. This risk is influenced by several factors, including the **virulence of the virus**, the **volume of blood transferred**, and the **efficacy of post-exposure prophylaxis (PEP)**. Understanding these factors is crucial for assessing the risk.

**Why the Correct Answer is Right**
The correct answer is based on studies that have quantified the risk of HIV transmission after a needlestick injury. The average risk is estimated to be about 0.3%, which translates to approximately 1 in 300 for a single incident. This risk is significantly lower than that for other bloodborne pathogens like hepatitis B. The **integrity of the skin**, the **depth of the wound**, and **immediate wound care** also play critical roles in determining the actual risk of transmission.

**Why Each Wrong Option is Incorrect**
**Option A:** This option overestimates the risk. While the risk is not negligible, it is not as high as 1 in 10.
**Option B:** This option underestimates the risk. The actual risk is higher than 1 in 1,000.
**Option D:** This option significantly underestimates the risk. The risk is substantially higher than 1 in 10,000.

**Clinical Pearl / High-Yield Fact**
It's crucial for healthcare workers to understand that prompt reporting and management of needlestick injuries can significantly reduce the risk of HIV transmission. **Post-exposure prophylaxis (PEP)**, when initiated promptly, can be highly effective in preventing the establishment of HIV infection.

**Correct Answer:** C. 0.3% or 1 in 300.