Which enterovirus causes acute hemorrhagic conjunctivitis (AHC)?

**Core Concept:** Acute Hemorrhagic Conjunctivitis (AHC) is an infectious disease primarily affecting the eyes caused by a virus. Enteroviruses are a group of viruses that can cause a wide range of diseases, including AHC.

**Why the Correct Answer is Right:** The correct answer (D) is the Coxsackievirus A16 (CVA16), which is a member of the Enterovirus genus within the Picornaviridae family. CVA16 infects the conjunctiva, leading to inflammation, edema, and hemorrhage, resulting in the characteristic symptoms of AHC.

**Why Each Wrong Option is Incorrect:**

A. Herpes simplex virus (HSV) is another virus that can cause infectious conjunctivitis but not AHC. HSV primarily targets the cornea, leading to a distinct clinical presentation.

B. Adenovirus is a common cause of conjunctivitis but not AHC. Adenoviruses primarily affect the respiratory tract and can cause ocular manifestations, but they are not specific to AHC.

C. Enterovirus D68 (EV-D68) is another enterovirus, but it is not known to cause AHC. EV-D68 primarily targets the respiratory tract and can cause respiratory symptoms, not ocular manifestations like AHC.

**Clinical Pearl / High-Yield Fact:** Infectious conjunctivitis is a common presentation in infectious diseases. Understanding the specific viruses causing these infections is essential for accurate diagnosis and appropriate management of patients.

**Correct Answer:** D. Coxsackievirus A16 (CVA16) causes acute hemorrhagic conjunctivitis (AHC) due to its specific tropism for conjunctiva.